Bugzilla

(In reply to Tooru Fujisawa [:arai] from comment #10)
> The problem (B) seems to be happening while opening `about:opentabs` in the following line,
> and if I open the URL, it shows some UI for a few frames and then the page becomes empty.
> 
> https://searchfox.org/firefox-main/rev/4bc9c2f9b62e7cb44894d581c8171edbf0f7e27f/browser/components/urlbar/tests/browser/browser_switchTab_override.js#146-149
> ```js
> let tab2 = await BrowserTestUtils.openNewForegroundTab(
>   gBrowser,
>   "about:opentabs"
> );
> ```
> 
> What does `about:opentabs` do when it's opened?
> Does it perform navigation quickly?
> Does it use custom elements and lit?

Hi! So the about:opentabs is supposed to be used when adding a new split view. With `browser.tabs.splitView.enabled` set to true and at least 2 tabs open, right click one of the tabs and select "Add Split View" in the context menu. This should display the page as expected. If the user doesn't have any other available tabs to be pulled into the split view or if a user tries to access about:opentabs outside of this context, we redirect to the new tab page.

(In reply to Tooru Fujisawa [:arai] from comment #10)
> The problem (B) seems to be happening while opening `about:opentabs` in the following line,
> and if I open the URL, it shows some UI for a few frames and then the page becomes empty.
> 
> https://searchfox.org/firefox-main/rev/4bc9c2f9b62e7cb44894d581c8171edbf0f7e27f/browser/components/urlbar/tests/browser/browser_switchTab_override.js#146-149
> ```js
> let tab2 = await BrowserTestUtils.openNewForegroundTab(
>   gBrowser,
>   "about:opentabs"
> );
> ```
> 
> What does `about:opentabs` do when it's opened?
> Does it perform navigation quickly?
> Does it use custom elements and lit?

Hi! So the about:opentabs is supposed to be used when adding a new split view. With `browser.tabs.splitView.enabled` set to true and at least 2 unpinned tabs open, right click one of the tabs and select "Add Split View" in the context menu. This should display the page as expected. If the user doesn't have any other available tabs to be pulled into the split view or if a user tries to access about:opentabs outside of this context, we redirect to the new tab page.