When saving the schematic, an error occurred: java.lang.ArrayIndexOutOfBoundsException: Index -66279751 out of bounds for length 117033984. The error did not recur upon attempting to save again.

Attaching the log:
crash-2025-02-02_01.12.56-client.txt

Do you mean using the exact same area selection, no modifications at all, it worked on the second try? How large exactly is the area you are saving?

@maruohon Yes. Saving the same area without any modifications worked on the second try.
The schematic size is 559x67x580.