Calc (18.104.22.168) opens a new spreadsheet with 1/16" high rows and columns maybe 1/4". (1) Where are Calc defaults set? (2) This happened after 3.6 install, over 3.5.
I remember an issue like this, but I can not remember the solution.
Try resetting the user profile.
Any chance you can try to update to our latest 4.0 build? I know that the 3.5 → 3.6 upgrade had some bad side effects for you, but perhaps the underlying issue has been resolved in the 4.0 branch.
If you’re like me, you accidentally zoomed out with the little zoom slider in the lower right hand corner.
Just adjust that to 100% and everything will look fine again.