Hi,
My first time creating a topic on this forum, please excuse any errors / oversights.
Today I encountered this error on Affinity Designer 1.8.5.703 on Windows 10.
I had 6 artboards in a file. I created slices and exported jpegs and closed the file. Later on when modifications were done to some of the artboards and ready for exporting slices again, the file kept on crashing when the slices panel was opened. On searching the forums for similar issues reported by others, I came across this (and other similar) thread(s):-
I think this issue was addressed earlier, but has resurfaced in this version. I updated Affinity Designer to 1.8.5.703 last Saturday (19th Sept 2020) from the earlier version 1.8.4.x.
Since my workflow (almost always) involves creating multiple artboards and exporting slices I can say with confidence that I have never encountered this issue earlier, i.e. since Nov 2019 when I began using Affinity Designer.
In the meanwhile, I copied the artwork to a new file and refrained from creating slices. The new file has been behaving OK.
Please let me know if you require additional inputs from me.