Workaround: pick the piece and move the finger upwards, then you can freely move it around (as in, instead of press-down-release, do press-up-down-release).

The pull to refresh has been very broken since forever. Apparently they enabled it by default in the latest version because it was "very stable" but I'm not so sure...

The drag down gesture in Firefox was disabled last year because it interfered with page content. Are you running an old version or did you explicitly re-enable that behavior somehow?

sorry to hear about that! do you mind sharing which device and version of android you're on? I believe what anilakar said is correct

Drag selection is problematic on mobile devices. Click and select is the way to go.