Opening Budget_sample.ods in LOOL demo. Selecting a row and after selecting a column, gives an unstable visualization, that stop clicking on any cell. The same happens selecting first a column and after a row. And same behavior with a new spreadsheet.
CONFIRMED on latest Firefox Dev build and the Collabora LOOL demo.
Fixed by the following commit: https://cgit.freedesktop.org/libreoffice/online/commit/?id=e27ae38bebf4b57aa7563357a188e33d0e1e0be8 Fix jumping after touch zooming also for mobile clients of normal Online
backported to libreoffice-6-2: 13256fd9a4843f242fde44c3bbc37687fd99b06d
There have been complications, this issue resurfaced, and required a follow-up fix, see bug 125304.