Why does a `click` event get triggered on my when I press Enter on it












6














I'm only adding a click event handler on my <button>.



HTML:



<button>Press <kbd>Enter</kbd> on me</button>


Javascript:



document.getElementsByTagName("button")[0].addEventListener("click", event => {

  event.preventDefault();



  console.log("Click:", event);

});


(Demo link)



Nevertheless, when I tab to the button in Firefox, then press Enter, I see the click event being fired. However, I cannot see this behaviour documented anywhere. Is this standard behaviour, and can I count on it working in all browsers?






javascript html dom accessibility dom-events







share|improve this question


















  • 1




    Try pressing the space bar when the button is in focus...another surprise..you clicked the button :-)
    – Thangadurai
    4 hours ago










  • Hehe yeah I got that, left it out for brevity :)
    – Vincent
    4 hours ago










  • keyboard geeks don't often use the mouse. Many even use vi-like addons to their browsers so that they can surf the web without ever touching their mouse. It's very frustrated when an app don't respond to keyboard events
    – phuclv
    26 mins ago
















6














I'm only adding a click event handler on my <button>.



HTML:



<button>Press <kbd>Enter</kbd> on me</button>


Javascript:



document.getElementsByTagName("button")[0].addEventListener("click", event => {

  event.preventDefault();



  console.log("Click:", event);

});


(Demo link)



Nevertheless, when I tab to the button in Firefox, then press Enter, I see the click event being fired. However, I cannot see this behaviour documented anywhere. Is this standard behaviour, and can I count on it working in all browsers?






javascript html dom accessibility dom-events







share|improve this question


















  • 1




    Try pressing the space bar when the button is in focus...another surprise..you clicked the button :-)
    – Thangadurai
    4 hours ago










  • Hehe yeah I got that, left it out for brevity :)
    – Vincent
    4 hours ago










  • keyboard geeks don't often use the mouse. Many even use vi-like addons to their browsers so that they can surf the web without ever touching their mouse. It's very frustrated when an app don't respond to keyboard events
    – phuclv
    26 mins ago














6












6








6







I'm only adding a click event handler on my <button>.



HTML:



<button>Press <kbd>Enter</kbd> on me</button>


Javascript:



document.getElementsByTagName("button")[0].addEventListener("click", event => {

  event.preventDefault();



  console.log("Click:", event);

});


(Demo link)



Nevertheless, when I tab to the button in Firefox, then press Enter, I see the click event being fired. However, I cannot see this behaviour documented anywhere. Is this standard behaviour, and can I count on it working in all browsers?






javascript html dom accessibility dom-events







share|improve this question













I'm only adding a click event handler on my <button>.



HTML:



<button>Press <kbd>Enter</kbd> on me</button>


Javascript:



document.getElementsByTagName("button")[0].addEventListener("click", event => {

  event.preventDefault();



  console.log("Click:", event);

});


(Demo link)



Nevertheless, when I tab to the button in Firefox, then press Enter, I see the click event being fired. However, I cannot see this behaviour documented anywhere. Is this standard behaviour, and can I count on it working in all browsers?






javascript html dom accessibility dom-events




javascript html dom accessibility dom-events






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked 4 hours ago









Vincent

1,26211628




1,26211628








  • 1




    Try pressing the space bar when the button is in focus...another surprise..you clicked the button :-)
    – Thangadurai
    4 hours ago










  • Hehe yeah I got that, left it out for brevity :)
    – Vincent
    4 hours ago










  • keyboard geeks don't often use the mouse. Many even use vi-like addons to their browsers so that they can surf the web without ever touching their mouse. It's very frustrated when an app don't respond to keyboard events
    – phuclv
    26 mins ago














  • 1




    Try pressing the space bar when the button is in focus...another surprise..you clicked the button :-)
    – Thangadurai
    4 hours ago










  • Hehe yeah I got that, left it out for brevity :)
    – Vincent
    4 hours ago










  • keyboard geeks don't often use the mouse. Many even use vi-like addons to their browsers so that they can surf the web without ever touching their mouse. It's very frustrated when an app don't respond to keyboard events
    – phuclv
    26 mins ago








1




1




Try pressing the space bar when the button is in focus...another surprise..you clicked the button :-)
– Thangadurai
4 hours ago




Try pressing the space bar when the button is in focus...another surprise..you clicked the button :-)
– Thangadurai
4 hours ago












Hehe yeah I got that, left it out for brevity :)
– Vincent
4 hours ago




Hehe yeah I got that, left it out for brevity :)
– Vincent
4 hours ago












keyboard geeks don't often use the mouse. Many even use vi-like addons to their browsers so that they can surf the web without ever touching their mouse. It's very frustrated when an app don't respond to keyboard events
– phuclv
26 mins ago




keyboard geeks don't often use the mouse. Many even use vi-like addons to their browsers so that they can surf the web without ever touching their mouse. It's very frustrated when an app don't respond to keyboard events
– phuclv
26 mins ago












2 Answers
2






active

oldest

votes


















6














This is largely because lots of authors have historically written code using click events while forgetting to account for users who don't click (whether because they prefer to use a keyboard to navigate, have a disability which makes it hard to use a pointing device, or whatever other reason).



The behaviour is documented in the HTML specification:




Certain elements in HTML have an activation behavior, which means that the user can activate them. This triggers a sequence of events dependent on the activation mechanism, and normally culminating in a click event, as described below.



…



For accessibility, the keyboard’s Enter and Space keys are often used to trigger an element’s activation behavior.




It then goes on to explain the steps in detail.






share|improve this answer























  • That's great, thanks for the reference - I will be relying on that for accessibility then!
    – Vincent
    4 hours ago










  • It's a very useful mechanism. If you plan to rely on it for accessibility, the caveat is that most elements do not have this default behaviour, so if you're using (say) a div or a span as a control, you'll have to add the key event handling yourself. (Be sure to add a role attribute too!)
    – brennanyoung
    3 hours ago






  • 1




    @brennanyoung — And make them keyboard accessible with tabindex … best to use elements designed to be interacted with in the first place!
    – Quentin
    3 hours ago






  • 1




    Quite right. You get a lot of accessibility 'for free' with <a>, <input> and <button>, but otherwise tabindex is just as important. Unfortunately, a11y implementation is far too rarely considered 'in the first place'.
    – brennanyoung
    3 hours ago










  • I switched from an <a> to a <button> for exactly this reason - to make sure I get the browser's a11y features for free. With tabindex, role and click and keydown event handlers, I'm sure I'd probably still have forgotten something, or would implement something incorrectly :)
    – Vincent
    3 hours ago





















3














Because for keyboard users (where mouse is not available), when a button is in focus and you press enter (possibly space as well) it simulates a click event.



This is the browsers accessibility support which most if not all browsers provide.






share|improve this answer



















  • 1




    "It's part of the ISO" — It isn't … and nobody uses ISO HTML anyway.
    – Quentin
    4 hours ago










  • @Quentin Removed. You're right, our workplace puts a big importance on the ISO hence the reference.
    – Adriani6
    4 hours ago










  • Ah sorry, I did not mean "why did they make it this way", but "why did browsers implement this - was it because it was standardised, or because they thought it was a good idea themselves". Apparently the former!
    – Vincent
    4 hours ago










  • @Vincent – The standard was defined after most browsers had already implemented it.
    – Quentin
    4 hours ago










  • I see. Well, that's great for me - saves me implementing keypress handlers myself :)
    – Vincent
    4 hours ago











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2 Answers
2






active

oldest

votes








2 Answers
2






active

oldest

votes









active

oldest

votes






active

oldest

votes









6














This is largely because lots of authors have historically written code using click events while forgetting to account for users who don't click (whether because they prefer to use a keyboard to navigate, have a disability which makes it hard to use a pointing device, or whatever other reason).



The behaviour is documented in the HTML specification:




Certain elements in HTML have an activation behavior, which means that the user can activate them. This triggers a sequence of events dependent on the activation mechanism, and normally culminating in a click event, as described below.



…



For accessibility, the keyboard’s Enter and Space keys are often used to trigger an element’s activation behavior.




It then goes on to explain the steps in detail.






share|improve this answer























  • That's great, thanks for the reference - I will be relying on that for accessibility then!
    – Vincent
    4 hours ago










  • It's a very useful mechanism. If you plan to rely on it for accessibility, the caveat is that most elements do not have this default behaviour, so if you're using (say) a div or a span as a control, you'll have to add the key event handling yourself. (Be sure to add a role attribute too!)
    – brennanyoung
    3 hours ago






  • 1




    @brennanyoung — And make them keyboard accessible with tabindex … best to use elements designed to be interacted with in the first place!
    – Quentin
    3 hours ago






  • 1




    Quite right. You get a lot of accessibility 'for free' with <a>, <input> and <button>, but otherwise tabindex is just as important. Unfortunately, a11y implementation is far too rarely considered 'in the first place'.
    – brennanyoung
    3 hours ago










  • I switched from an <a> to a <button> for exactly this reason - to make sure I get the browser's a11y features for free. With tabindex, role and click and keydown event handlers, I'm sure I'd probably still have forgotten something, or would implement something incorrectly :)
    – Vincent
    3 hours ago


















6














This is largely because lots of authors have historically written code using click events while forgetting to account for users who don't click (whether because they prefer to use a keyboard to navigate, have a disability which makes it hard to use a pointing device, or whatever other reason).



The behaviour is documented in the HTML specification:




Certain elements in HTML have an activation behavior, which means that the user can activate them. This triggers a sequence of events dependent on the activation mechanism, and normally culminating in a click event, as described below.



…



For accessibility, the keyboard’s Enter and Space keys are often used to trigger an element’s activation behavior.




It then goes on to explain the steps in detail.






share|improve this answer























  • That's great, thanks for the reference - I will be relying on that for accessibility then!
    – Vincent
    4 hours ago










  • It's a very useful mechanism. If you plan to rely on it for accessibility, the caveat is that most elements do not have this default behaviour, so if you're using (say) a div or a span as a control, you'll have to add the key event handling yourself. (Be sure to add a role attribute too!)
    – brennanyoung
    3 hours ago






  • 1




    @brennanyoung — And make them keyboard accessible with tabindex … best to use elements designed to be interacted with in the first place!
    – Quentin
    3 hours ago






  • 1




    Quite right. You get a lot of accessibility 'for free' with <a>, <input> and <button>, but otherwise tabindex is just as important. Unfortunately, a11y implementation is far too rarely considered 'in the first place'.
    – brennanyoung
    3 hours ago










  • I switched from an <a> to a <button> for exactly this reason - to make sure I get the browser's a11y features for free. With tabindex, role and click and keydown event handlers, I'm sure I'd probably still have forgotten something, or would implement something incorrectly :)
    – Vincent
    3 hours ago
















6












6








6






This is largely because lots of authors have historically written code using click events while forgetting to account for users who don't click (whether because they prefer to use a keyboard to navigate, have a disability which makes it hard to use a pointing device, or whatever other reason).



The behaviour is documented in the HTML specification:




Certain elements in HTML have an activation behavior, which means that the user can activate them. This triggers a sequence of events dependent on the activation mechanism, and normally culminating in a click event, as described below.



…



For accessibility, the keyboard’s Enter and Space keys are often used to trigger an element’s activation behavior.




It then goes on to explain the steps in detail.






share|improve this answer














This is largely because lots of authors have historically written code using click events while forgetting to account for users who don't click (whether because they prefer to use a keyboard to navigate, have a disability which makes it hard to use a pointing device, or whatever other reason).



The behaviour is documented in the HTML specification:




Certain elements in HTML have an activation behavior, which means that the user can activate them. This triggers a sequence of events dependent on the activation mechanism, and normally culminating in a click event, as described below.



…



For accessibility, the keyboard’s Enter and Space keys are often used to trigger an element’s activation behavior.




It then goes on to explain the steps in detail.







share|improve this answer














share|improve this answer



share|improve this answer








edited 4 hours ago

























answered 4 hours ago









Quentin

640k718611032




640k718611032












  • That's great, thanks for the reference - I will be relying on that for accessibility then!
    – Vincent
    4 hours ago










  • It's a very useful mechanism. If you plan to rely on it for accessibility, the caveat is that most elements do not have this default behaviour, so if you're using (say) a div or a span as a control, you'll have to add the key event handling yourself. (Be sure to add a role attribute too!)
    – brennanyoung
    3 hours ago






  • 1




    @brennanyoung — And make them keyboard accessible with tabindex … best to use elements designed to be interacted with in the first place!
    – Quentin
    3 hours ago






  • 1




    Quite right. You get a lot of accessibility 'for free' with <a>, <input> and <button>, but otherwise tabindex is just as important. Unfortunately, a11y implementation is far too rarely considered 'in the first place'.
    – brennanyoung
    3 hours ago










  • I switched from an <a> to a <button> for exactly this reason - to make sure I get the browser's a11y features for free. With tabindex, role and click and keydown event handlers, I'm sure I'd probably still have forgotten something, or would implement something incorrectly :)
    – Vincent
    3 hours ago




















  • That's great, thanks for the reference - I will be relying on that for accessibility then!
    – Vincent
    4 hours ago










  • It's a very useful mechanism. If you plan to rely on it for accessibility, the caveat is that most elements do not have this default behaviour, so if you're using (say) a div or a span as a control, you'll have to add the key event handling yourself. (Be sure to add a role attribute too!)
    – brennanyoung
    3 hours ago






  • 1




    @brennanyoung — And make them keyboard accessible with tabindex … best to use elements designed to be interacted with in the first place!
    – Quentin
    3 hours ago






  • 1




    Quite right. You get a lot of accessibility 'for free' with <a>, <input> and <button>, but otherwise tabindex is just as important. Unfortunately, a11y implementation is far too rarely considered 'in the first place'.
    – brennanyoung
    3 hours ago










  • I switched from an <a> to a <button> for exactly this reason - to make sure I get the browser's a11y features for free. With tabindex, role and click and keydown event handlers, I'm sure I'd probably still have forgotten something, or would implement something incorrectly :)
    – Vincent
    3 hours ago


















That's great, thanks for the reference - I will be relying on that for accessibility then!
– Vincent
4 hours ago




That's great, thanks for the reference - I will be relying on that for accessibility then!
– Vincent
4 hours ago












It's a very useful mechanism. If you plan to rely on it for accessibility, the caveat is that most elements do not have this default behaviour, so if you're using (say) a div or a span as a control, you'll have to add the key event handling yourself. (Be sure to add a role attribute too!)
– brennanyoung
3 hours ago




It's a very useful mechanism. If you plan to rely on it for accessibility, the caveat is that most elements do not have this default behaviour, so if you're using (say) a div or a span as a control, you'll have to add the key event handling yourself. (Be sure to add a role attribute too!)
– brennanyoung
3 hours ago




1




1




@brennanyoung — And make them keyboard accessible with tabindex … best to use elements designed to be interacted with in the first place!
– Quentin
3 hours ago




@brennanyoung — And make them keyboard accessible with tabindex … best to use elements designed to be interacted with in the first place!
– Quentin
3 hours ago




1




1




Quite right. You get a lot of accessibility 'for free' with <a>, <input> and <button>, but otherwise tabindex is just as important. Unfortunately, a11y implementation is far too rarely considered 'in the first place'.
– brennanyoung
3 hours ago




Quite right. You get a lot of accessibility 'for free' with <a>, <input> and <button>, but otherwise tabindex is just as important. Unfortunately, a11y implementation is far too rarely considered 'in the first place'.
– brennanyoung
3 hours ago












I switched from an <a> to a <button> for exactly this reason - to make sure I get the browser's a11y features for free. With tabindex, role and click and keydown event handlers, I'm sure I'd probably still have forgotten something, or would implement something incorrectly :)
– Vincent
3 hours ago






I switched from an <a> to a <button> for exactly this reason - to make sure I get the browser's a11y features for free. With tabindex, role and click and keydown event handlers, I'm sure I'd probably still have forgotten something, or would implement something incorrectly :)
– Vincent
3 hours ago















3














Because for keyboard users (where mouse is not available), when a button is in focus and you press enter (possibly space as well) it simulates a click event.



This is the browsers accessibility support which most if not all browsers provide.






share|improve this answer



















  • 1




    "It's part of the ISO" — It isn't … and nobody uses ISO HTML anyway.
    – Quentin
    4 hours ago










  • @Quentin Removed. You're right, our workplace puts a big importance on the ISO hence the reference.
    – Adriani6
    4 hours ago










  • Ah sorry, I did not mean "why did they make it this way", but "why did browsers implement this - was it because it was standardised, or because they thought it was a good idea themselves". Apparently the former!
    – Vincent
    4 hours ago










  • @Vincent – The standard was defined after most browsers had already implemented it.
    – Quentin
    4 hours ago










  • I see. Well, that's great for me - saves me implementing keypress handlers myself :)
    – Vincent
    4 hours ago
















3














Because for keyboard users (where mouse is not available), when a button is in focus and you press enter (possibly space as well) it simulates a click event.



This is the browsers accessibility support which most if not all browsers provide.






share|improve this answer



















  • 1




    "It's part of the ISO" — It isn't … and nobody uses ISO HTML anyway.
    – Quentin
    4 hours ago










  • @Quentin Removed. You're right, our workplace puts a big importance on the ISO hence the reference.
    – Adriani6
    4 hours ago










  • Ah sorry, I did not mean "why did they make it this way", but "why did browsers implement this - was it because it was standardised, or because they thought it was a good idea themselves". Apparently the former!
    – Vincent
    4 hours ago










  • @Vincent – The standard was defined after most browsers had already implemented it.
    – Quentin
    4 hours ago










  • I see. Well, that's great for me - saves me implementing keypress handlers myself :)
    – Vincent
    4 hours ago














3












3








3






Because for keyboard users (where mouse is not available), when a button is in focus and you press enter (possibly space as well) it simulates a click event.



This is the browsers accessibility support which most if not all browsers provide.






share|improve this answer














Because for keyboard users (where mouse is not available), when a button is in focus and you press enter (possibly space as well) it simulates a click event.



This is the browsers accessibility support which most if not all browsers provide.







share|improve this answer














share|improve this answer



share|improve this answer








edited 4 hours ago

























answered 4 hours ago









Adriani6

4,34421327




4,34421327








  • 1




    "It's part of the ISO" — It isn't … and nobody uses ISO HTML anyway.
    – Quentin
    4 hours ago










  • @Quentin Removed. You're right, our workplace puts a big importance on the ISO hence the reference.
    – Adriani6
    4 hours ago










  • Ah sorry, I did not mean "why did they make it this way", but "why did browsers implement this - was it because it was standardised, or because they thought it was a good idea themselves". Apparently the former!
    – Vincent
    4 hours ago










  • @Vincent – The standard was defined after most browsers had already implemented it.
    – Quentin
    4 hours ago










  • I see. Well, that's great for me - saves me implementing keypress handlers myself :)
    – Vincent
    4 hours ago














  • 1




    "It's part of the ISO" — It isn't … and nobody uses ISO HTML anyway.
    – Quentin
    4 hours ago










  • @Quentin Removed. You're right, our workplace puts a big importance on the ISO hence the reference.
    – Adriani6
    4 hours ago










  • Ah sorry, I did not mean "why did they make it this way", but "why did browsers implement this - was it because it was standardised, or because they thought it was a good idea themselves". Apparently the former!
    – Vincent
    4 hours ago










  • @Vincent – The standard was defined after most browsers had already implemented it.
    – Quentin
    4 hours ago










  • I see. Well, that's great for me - saves me implementing keypress handlers myself :)
    – Vincent
    4 hours ago








1




1




"It's part of the ISO" — It isn't … and nobody uses ISO HTML anyway.
– Quentin
4 hours ago




"It's part of the ISO" — It isn't … and nobody uses ISO HTML anyway.
– Quentin
4 hours ago












@Quentin Removed. You're right, our workplace puts a big importance on the ISO hence the reference.
– Adriani6
4 hours ago




@Quentin Removed. You're right, our workplace puts a big importance on the ISO hence the reference.
– Adriani6
4 hours ago












Ah sorry, I did not mean "why did they make it this way", but "why did browsers implement this - was it because it was standardised, or because they thought it was a good idea themselves". Apparently the former!
– Vincent
4 hours ago




Ah sorry, I did not mean "why did they make it this way", but "why did browsers implement this - was it because it was standardised, or because they thought it was a good idea themselves". Apparently the former!
– Vincent
4 hours ago












@Vincent – The standard was defined after most browsers had already implemented it.
– Quentin
4 hours ago




@Vincent – The standard was defined after most browsers had already implemented it.
– Quentin
4 hours ago












I see. Well, that's great for me - saves me implementing keypress handlers myself :)
– Vincent
4 hours ago




I see. Well, that's great for me - saves me implementing keypress handlers myself :)
– Vincent
4 hours ago


















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濃尾地震

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濃尾地震 『岐阜市街大地震之図』 歌川国利画 本震 発生日 1891年（明治24年）10月28日 発生時刻 6時38分50秒（JST） 震央 日本 岐阜県本巣郡西根尾村（現・本巣市） 北緯35度35分 東経136度20分（ 地図 ） 規模    マグニチュード（M）8.0 最大震度    震度7： 注1 福井県今立郡鯖江町、愛知県葉栗郡大田島村、東春日井郡勝川村 地震の種類 直下型地震 被害 死傷者数 死者7,273人、負傷者17,175人 注1：当時の震度階級では「激烈」 プロジェクト:地球科学 プロジェクト:災害 テンプレートを表示 濃尾地震 （のうびじしん）は、1891年（明治24年）10月28日に濃尾地方で発生した、日本史上最大の内陸地殻内地震。「 美濃・尾張地震 （みの・おわりじしん）」とも呼ばれている。辛卯の年に発生したことから 辛卯震災 と呼んでいる報告書もある。 目次 1 概要 1.1 震源断層 2 被害 3 各地の震度 4 前兆現象 5 報道 6 学術的な意義 7 地震防災 8 脚注 9 関連項目 10 外部リンク 概要 濃尾地震発生当時の根尾谷断層 濃尾地震を引き起こした根尾谷断層 写真中央を斜めに走る段差が根尾谷断層 濃尾地震は、1891年10月28日6時38分50秒に発生した。震源は、岐阜県本巣郡西根尾村（現・本巣市）、北緯35度35分、東経136度20分付近。河角廣 (1951) は岐阜市付近（北緯35.6度、東経136.6度）に震央を仮定し規模 M K = 7.0 を与え [1] 、マグニチュードは M = 8.4 に換算されているが、明治・大正期の地震については0.5程度大きく見積もられているとされる [2] 。また、震央距離と震度との関係など当時のデータから後にM8.0 [3] とも推定される。アメリカ地質調査所 (USGS) でも8.0としている [4] 。「根尾谷断層帯」が活動した典型的な内陸地殻内地震（いわゆる直下型地震）であり、これは記録が残っている日本の内陸
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How to rewrite equation of hyperbola in standard form

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2 $begingroup$ I was wondering about this question: $$ 9 x ^ 2 -4y^2-72x=0 $$ What is the step-by-step process of writing such an equation which, in this case, has the graph of a hyperbola in standard form? Please excuse me for my messy equation. As I am relatively new to Mathematics Stack Exchange, I do not know how to insert superscripts. Thank you ahead of time! calculus conic-sections share | cite | improve this question edited 2 hours ago Key Flex 8,637 6 12 33 asked 2 hours ago
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No ethernet ip address in my vocore2

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0 I just flashed my vocore2u with openwrt 18.06.1, and plug it with an ethernet cable to access network while setting up wireless access-point for my phone. The AP is working and connected to the network, but the ip in my phone is in the subnet of another router. And there's no ip assigned to my vocore2 so I cannot ssh into it. After connecting to vocore2 with serial terminal, ping 8.8.8.8 is also failed. How can I make my vocore2 gain ip from the router and setting up the network well? root@OpenWrt:/etc/config# ifconfig apcli0 Link encap:Ethernet HWaddr BA:D8:12:07:01:71 inet6 addr: fe80::b8d8:12ff:fe07:171/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 erro
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