Interesting question about running Affinity apps on Linux! Like @dfrazer said, it’s possible, but it’s currently not working well enough to actually be usable by the sounds of it (you can edit, but can’t save your edited file). đ Hopefully in the future it will get better.
https://forum.affinity.serif.com/index.php?/topic/166159-affinity-photo-running-on-linux-with-bottles/
https://forum.affinity.serif.com/index.php?/topic/47502-affinity-products-for-linux/&do=findComment&comment=940833
