I have been using version 5.0.8 on an Acer laptop running Ubuntu 20.04 and moved to an Acer Chromebook which has a beta version Debian Buster. Unfortunately the latest version of Kmymoney available on Buster is 5.03 and when I tried to load the files I have saved using 5.0.8 I get the error "File was not parsable! /build/kmymoney-yzwQi1/kmymoney-5.0.3/kmymoney/plugins/xml/mymoneystoragexml.cpp:1396". Is there a plugin that will allow the file to be opened or is there a way to downgrade the saved file to version 5.0.3?

This actually should not happen (but you never know). An alternative for you might be to use the latest AppImage version of KMyMoney. Let us know, if that helped to solve your problem.

Sorry I took a long time to get to your reply. I found that the Appimage works fine. Thank you.