OK! Here’s one thing I can repro, OnePlus 6, everything at latest updated versions:
When the Chrome address bar is suppressed (via scrolling down), I cannot tap on the bottom-most area in the Chrome viewport where the minimized composer is. It’s physically impossible, my taps don’t register at all!
I have to scroll the viewport up, to bring the Chrome address bar back. Then, and only then, am I able to tap on the area at the bottom of the viewport where the minimized composer is.
So the repro is:
- Start composing a reply, type some text in the reply box
- Minimize composer.
- Scroll down ↓ to force the address bar to disappear.
- Try tapping on the minimized composer at the bottom of the viewport; you won’t be able to.
- Scroll up ↑ to force the address bar to reappear.
- Try tapping on the minimized composer at the bottom of the viewport, it will work fine.
TL;DR there appear to be internal bugs in Android Chrome around the address bar appearing or not appearing, causing it to calculate taps wrong, offset by exactly the address bar height. As a workaround, make sure the address bar is visible by scrolling ↑ up.