One issue I had while using LibreOffice Calc on Windows 11 is that there was some incredible lag whenever my mouse cursor is hovering over the application. This is on a new document, a blank spreadsheet with nothing in it.
It's enough lag to make the cursor freeze for a moment while moving it around, which is strange because there shouldn't be any processing the CPU could do on an empty sheet that would lead to that, meaning that this is most likely the processing freezing while waiting for another hardware component or slow resource to respond.
It turns out the reason for this is that "Skia" is enabled. Skia is a 2D graphics library that LibreOffice Calc uses to create its graphical user interface. I assume this includes the menubar, since even the menubar was lagging when I hovered my mouse cursor over it.
How to Fix
To fix this issue, follow the following steps:
1: go to Tools -> Options on the menubar. This will open LibreOffice Calc's options dialog window, which has a list-detail layout.
2: on the list pane, select on LibreOffice -> View. You should see view options on the detail pane.
3: uncheck "Use Skia for all rendering." You'll be told that you must restart LibreOffice Calc for the setting to apply. Done that, the issue should be fixed.
If it isn't fixed, then I'm sorry but I can't help you. Try asking for help on LibreOffice's official forums.
Observations
The option "Force Skia software rendering" also works, but makes the text blurry.
With this in consideration it's very likely that the problem is with hardware-accelerated graphics. My graphics card is an Nvidia GTX 1050ti, and I think I never had issues with LibreOffice Calc on Linux, so it could be that this specific combination of hardware and operating system causes issues with Calc or Skia.