Setting: expand category/section with long sub-categories list shrinks the whole Theia page app length --> no main menu

[safisa]

Bug Description:

Hi,
This is a strange issue, on the latest Theia build (master).

Steps to Reproduce:

1. open the browser app
2. open the setting panel
3. expand the extensions category
4. the whole page length shrinks --> the main menu is not visible
5. click on a different view than the selected view (explorer) in the left panel, e.g. search, the page length gets back to its normal and the main menu is visible again
6. expand the AI Feature in the setting, it will shrink again...

Additional Information

• Operating System: Mac - Chrome
• Theia Version: Latest master

[sdirix]

Thanks for the report!

[JonasHelming]

I seems to only happen when the explorer is selected. And then it always happens if you change the selection in the settings view.

[JonasHelming]

Could be related to Lumino upgrade, to #15223 or to the recent setting additions.

[tsmaeder]

Strangely, I was able to reproduce this in electron with custom title bar mode, but not anymore. Still happens in browser version.

[tsmaeder]

Expanding the section in the settings scrolls the windows object (window.scrollY) up about 26 pixels. The window is scrolled, not resized, as you can see by the white space of the same height appearing at the bottom. Not sure how this behiour is happening.

[tsmaeder]

Scrolling also seems to cause #15271, but we can't really fix window scrolling with css. It feels important to understand why the scrolling occurs.