Add option the popup to close on mouseleave

[darkred]

Closes #123

Test URLs

https://github.com/

Screenshot

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Note to reviewers

I use .removeAttribute('open') to close the dropdown.

[fregante]

Thank you! I’ll make sure it works correctly soon

[darkred]

I made a change so that the popup close gets canceled if you re-mousenter quick enough, within 1 sec (1000 ms)
(and updated the screenshot in the OP).

[darkred]

Hi @fregante
Is there any way I can assist you in making the PR complete ?

 
Some notes:

• About the popup closing to be canceled if you re-mousenter quick enough,
  the interval I currently have is 1000 msec, but I think it should be 500 msec. What do you think?

• If I click a "Mark as done" and then move the mouse away so that the popup gets closed,
  then if I move the mouse to reopen the popup, clicking another "Mark as done"
  unfortunately causes the relevant "Marked x notifications as read" message to be displayed multiple times: e.g.
  
  So, I tried changing removeAttribute() into remove() the popup altogether + reopening it (see code below)
  but unfortunately the issue remains:

  using remove() :

  		if (options.closeOnMouseleave) {
  			let timer;
  			select('.NPG-dropdown').addEventListener('mouseleave', () => {
  				// timer = setTimeout(closeDropdown, 500);
  				timer = setTimeout(() => {closeDropdown(); createNotificationsDropdown();}, 500);
  			});
  			select('.NPG-dropdown').addEventListener('mouseenter', () => {
  				clearTimeout(timer);
  			});
  		}
  
  // ...
  
  function closeDropdown() {
  	// select('.NPG-container[open]').removeAttribute('open');
  	select('.NPG-container').remove();
  }

[darkred]

Thank you! I’ll make sure it works correctly soon

@fregante Have you changed your mind? Do you find this PR is not salvageable? Should I close this?

[fregante]

I've been on Safari for a year and I haven't used some of my extensions since 😅 so you can just leave this open until someone reviews it

[tjx666]

Welcome to contribute here: https://github.com/tjx666/github-notifications-preview/tree/main

[fregante]

I just submitted this version to the chrome web store. They should publish it within 24 hours