Affinity Photo crashes and all your data is lost if you use the gradient tool not 'properly'.
Tested under macOS Mojave 10.14.6 (latest) , Affinity Photo 1.7.2 (latest) and 1.7.1:
1) make new document
2) add a pixel layer
3) select gradient tool
4) draw a line for the gradient
5) select the swatches tab
6) select a color and drag it to one end of the line of the gradient
-> Affinity Photo crashes and all your work is lost
Dear Affinity developers:
Please fix this behaviour! I'm not interested in a workaround! (I know how to 'properly'/'without crashing' use the gradient tool.) Prevent Affinity Photo from crashing.
Maybe do nothing or send an error-message if the user input can not be handled by the program but don't crash. If you are forward thinking make it possible to restore your work (at least some older version) if the program crashes. Maybe look at concepts like Final Cut Pro where saving documents ist handled by the program not the user. Modern software users don't want to handle that crap. You are a huge step in the right direction (compared to other Software) but please don't stop here and continue this great path ;-)