Calc toolbar and worksheet slightly move up and down

I worked in two Calc windows, and their toolbars and worksheets were shifting up and down by a couple of pixels whenever I switched between them. Quite annoying.

I noticed it would start happening after the LibreOffice Update bubble pops up in the top right corner, because it plants some invisible icon there that pushes the UI down.

To get rid of annoying UI movements, go to Tools / Options / LibreOffice / Online Update / uncheck Check for updates automatically

It is most possibly OS- and/or OpenGL-dependent. Please post your OS info, and full information from Help->About. Possibly you’d need to file a bug report (if it turns out to be reproducible with later version - I cannot reproduce with Version: 6.2.2.1 (x64)
Build ID: fcd633fb1bf21b0a99c9acb3ad6e526437947b01
CPU threads: 12; OS: Windows 10.0; UI render: default; VCL: win;
Locale: ru-RU (ru_RU); UI-Language: en-US
Calc: CL). Thanks.

Version: 5.4.5.1
Build ID: 79c9829dd5d8054ec39a82dc51cd9eff340dbee8
CPU threads: 4; OS: Windows 6.2; UI render: default;
Locale: en-CA (en_CA); Calc: CL

Version: 6.1.4.2
Build ID: 9d0f32d1f0b509096fd65e0d4bec26ddd1938fd3
CPU threads: 4; OS: Windows 10.0; UI render: default;
Locale: en-US (en_CA); Calc: CL

@librenewbie, Post the answer below, in Add Answer.