Upon installing LO 25.2.3.2 in Apple silicone iMac, I manually corrected my templates’ background color from black (hex 000000) to white (hex ffffff). However, all calc sheets previous to that installation are cluttered with random blocks of blacked-out cells.
Manually formatting the background color of blacked-out blocks from black to white does restore calc readability.
As my calc document has many thousands of entries, manual restoration is untenable.
Is there a background color test to automatically convert cell background color which is not dependant on cell numerical value ?
Thanks ! Rob Glass
an example would help 
Test if changing the Appearance>Theme could help, sometimes after install 25.2 changing the Theme applying it, solves the issue.
Usually this happens when we “clear” a cell background color with the color that we see (black in this case), and not with no fill.
The default Find and Replace dialog (version 24.2) don’t has the capability to found background colors. Maybe you must use a macro.
Next time you turn to dark mode, you will see the “whited-out” cells. It is better to work with cell styles.
Dear LeRoyG,
Thank you for your helpful reply.
Despite my limited skills in using all of LO’s rich features, I’m aspirational. Macros and styles are sometime in my future.
I found a possible solution for my particular situation: LO/Preferences/Appearance/Customization/Document Background/Color/White.
Thanks !
Rob Glass
37 Coult Lane
Old Lyme, CT
06371
Ph (212-203-9329)