settings buttons very unreliable in iPhone

[foliovision]

User story would be: Make settings more reliable in iPhone

Test bed is iOS 13.5 on an iPhone 11 Pro Max. Server side it's WordPress 5.7.x, editing in plain text mode (no Classic Editor, no Gutenberg). The good news is that with HESH enabled, it's much easier to edit a post – generally it's hard to make the WordPress post field accept a cursor. With HESH it's very easy to place the cursor.

On the other hand, it's very hard to make the settings buttons work at all (they open but then for instance the number button must be pressed five to ten times and works randomly). After changing settings it's impossible to close the settings dialogue (the black X just won't close no matter how many times I touch it gently or stab it). The only way to start editing again is to reload the page (it is possible to save changes before reloading so it's not a critical bug but a very great nuisance).

I would be fine with having the setting somewhere else as on the editor page as generally I keep my settings always the same way. As we don't use the WordPress code editor for themes and plugins (work via SFTP with BBEdit and VSCodium), disable the code editor, our requirements for settings in the post editor are considerably lower. Syntax highlighting is mainly what we are after, as well as being able to choose a font size.

All of this works just fine on the same website in desktop mode (MacOS X 10.14.6, Chromium 89) so it's not an issue with the website.