Placeholder text overlaps the list element in toggle list on mobile

[isugic]

Describe the bug
The placeholder test overlaps the second element in the list

To Reproduce

1. On your mobile device: Type / to open the menu

2. Select Toggle list

3. Create a list of at least two elements one after another without collapsing them

4. Collapse the first one

Expected behavior
There should not be any overlapping

[MDSAM05]

Hi! I reproduced this issue on mobile and implemented a fix.
The overlapping placeholder happens because the .bn-inline-content marker does not reposition correctly inside collapsed toggles under 600px width.

If you want, I can open a Pull Request with this patch.`

[nperez0111]

@MDSAM05 feel free to open a PR with your fix, I'll be happy to review it

[woutervroege]

PR: #2291