Bugzilla

I see a similar hang in Chrome with the same steps (be logged into github, load the URL, scroll to the end of the page, notice throbber spinning for ~8-10 seconds, during which time the tab is not responsive to user input e.g. clicks/text-selection).

So: I do see something like what was reported, but it reproduces in multiple browsers -- not just Firefox -- and it seems to be due to GitHub just performing a lot of synchronous work in JS all at once.  So, my profile from comment 3 isn't especially-useful except to demonstrate what GitHub is doing (which seems to be slow regardless of browser).

(In reply to joshuasend1 from comment #0)
> Expected the page to load < 1 second. This worked in older versions of Firefox, and works fine in Safari/Chrome.

To clarify: is it still faster in those other browsers if you're logged in to GitHub? And are you sure you're testing with the same steps there? (I assume in Firefox you're triggering the GitHub lazy-load-the-bottom-of-the-diff behavior, perhaps by scrolling to near the end of the page, or maybe something else).

Also, it is notable that your reported load time (minutes) is much longer than what I'm seeing, so a profile would still definitely be handy, per emilio's comment! Though, that's perhaps unnecessary if you discover that other browsers do in fact trigger a similar hang under the same conditions, since that would indicate it's an issue on GitHub's side.

I see a similar hang in Chrome with the same steps (be logged into github, load the URL, scroll to the end of the page, notice throbber spinning for ~8-10 seconds, during which time the tab is not responsive to user input e.g. clicks/text-selection).

So: I do see something like what was reported, but it reproduces in multiple browsers -- not just Firefox -- and it seems to be due to GitHub just performing a lot of synchronous work in JS all at once.  So, my profile from comment 3 isn't especially-useful except to demonstrate what GitHub is doing (which seems to be slow regardless of browser).

(In reply to joshuasend1 from comment #0)
> Expected the page to load < 1 second. This worked in older versions of Firefox, and works fine in Safari/Chrome.

To clarify: is it still faster in those other browsers if you're logged in to GitHub? And are you sure you're testing with the same steps there? (I assume in Firefox you're triggering the GitHub lazy-load-the-bottom-of-the-diff behavior, perhaps by scrolling to near the end of the page, or maybe something else).

Also, it is notable that your reported load time (minutes) is much longer than what I'm seeing, so a profile would still definitely be handy, per emilio's comment! Though, that's perhaps unnecessary if you discover that other browsers do in fact trigger a similar hang when tested under the exact same conditions, since that would indicate it's an issue on GitHub's side.

I see a similar hang in Chrome (similar to the one I see in comment 3), if I perform the same steps (be logged into github, load the URL, scroll to the end of the page, notice throbber spinning for ~8-10 seconds, during which time the tab is not responsive to user input e.g. clicks/text-selection).

So: I do see something like what was reported, but it reproduces in multiple browsers -- not just Firefox -- and it seems to be due to GitHub just performing a lot of synchronous work in JS all at once.  So, my profile from comment 3 isn't especially-useful except to demonstrate what GitHub is doing (which seems to be slow regardless of browser).

(In reply to joshuasend1 from comment #0)
> Expected the page to load < 1 second. This worked in older versions of Firefox, and works fine in Safari/Chrome.

To clarify: is it still faster in those other browsers if you're logged in to GitHub? And are you sure you're testing with the same steps there? (I assume in Firefox you're triggering the GitHub lazy-load-the-bottom-of-the-diff behavior, perhaps by scrolling to near the end of the page, or maybe something else).

Also, it is notable that your reported load time (minutes) is much longer than what I'm seeing, so a profile would still definitely be handy, per emilio's comment! Though, that's perhaps unnecessary if you discover that other browsers do in fact trigger a similar hang when tested under the exact same conditions, since that would indicate it's an issue on GitHub's side.