window sizing function impaired

I have no clue what happened, but the button to resize the window minimizes
LO, and I can only maximize it to full screen, resizing it no longer works,
and I have no clue how I caused this.

Windows or Mac or Linux? Which window manager? Problem persists after
reboot? There's a great essay out there, How To Ask Questions The Smart

Clarification, this is on Linx Mint 20.3 Una/Cinnamon

It gets even more bizarre, this happens only in calc, the spreadsheet, not
in writer.