The issue concerns a bug in the mobile view editor where the cog dropdown menu fails to display properly, instead causing the editor button bar to become vertically scrollable. Users piffy, Benjamin_D, JammyDodger, and Don report the issue on Android Chrome, both on production and meta, with the problem occurring in safe mode. The bug is tied to the overflow-x: auto; property on the .d-editor-button-bar container, which hides the dropdown menu on mobile due to its position: absolute styling, unlike desktop where position: fixed works correctly. awesomerobot identifies the root cause and proposes a fix by removing the overflow-x: auto; property on mobile, with a commit already made to address the issue. The team is still considering long-term solutions to handle toolbar overflow on mobile.
I entered safe mode on mobile view. While replying to a post, the editor has the cog option at the end. When I tap it, the d-editor-button-bar becomes vertically scrollable instead of displaying a dropdown of the extra options.
The menu is positioned differently on desktop (position: fixed) vs mobile (position: absolute) so because of CSS magic the overflow-x: auto; on the .d-editor-button-bar container was hiding the menu on mobile but has no effect on desktop.
That overflow-x: auto; property fixes this issue on desktop:
I just added a fix that shows the menu again on mobile by removing overflow-x: auto;