Gutenberg: iOS browser font size selector does not work

[rezzap]

Steps to reproduce

1. Starting at URL: https://wordpress.com/block-editor/post/ in a mobile browser (tested this on iOS, but user reporting is working on Android)
2. Add a new paragraph block to a post.
3. Click on 'block settings' to open the font-size options to select through preset font size (small, medium, large)
4. Nothing happens.

What I expected

I expected a menu to open like in the desktop browser to select different options.

What happened instead

Nothing happens and it is not possible to select a different font size.

You can select the font-size number and reset button, but the preset values doesn't work.

Browser / OS version

Replicated the issue in both Chrome (71.0.3578.89) and Safari iOS12.1.2 on iPhone X

Screenshot / Video

Context / Source

#user-report in zen-1672232

[arunsathiya]

I tested this on an Android smartphone, and I am not able to get that selector to work.

I also tried reducing the viewport on Google Chrome Version 71.0.3578.98 (Official Build) (64-bit) for macOS 10.14.2 - Mac OS Mojave, and I see the same behaviour. It works when I launch the browser console though using Option + Command + J - unsure why it works only for this stage.

Moreover, this seems to be a core Gutenberg issue as I am able to reproduce this on a core install. Leaving this issue open for an additional check from someone else.

[gwwar]

@arunsathiya If we can reproduce on vanilla Gutenberg, let's close this issue, open an issue there, and we can keep track of the core issue in the backlog.

Let me know if you need any help with that!

[arunsathiya]

Sounds good! I have reported it at WordPress/gutenberg#13155