TOP button (transparent floating)

i use Opera Beta and Opera on my phone, and both just updated to chromium 54 (i think?) in the last couple days. since then, the transparent floating Up button (top of page) had stopped working, although it still shows.

is this indeed another chromium issue? too bad, i use that button frequently and am now hitting everything it floats over.

any possible fix for that? thank you.

 

ok now it works.

but i don't know why. i didn't even reboot.

EDIT:
the funny thing is that i watched this for about 36hrs and had multiple reboots & data clears before reporting it. i thought it was stable. i dunno.

as of now it appears that all overlays like the TOP button and the new message bubble notification at the bottom are intermittently functioning. no function maybe 2 of 3 times.