I've noticed recently that on Firefox for Android the forum post editor is pretty broken. The font changes size as you type, and its pretty much impossible to reposition the cursor to correct typos or insert text. The cursor appears to move to where you touch, but new text appears at the end of the post or sometimes at other positions.
Firefox 88.1.2 from the Play Store on Android 10.
I like the redesign and appreciate all the work that goes into the site. Just thought the devs should know.