When we upgraded from 19.x.x.x we had to regenerate all of our themes in the process applications. A bunch of properties were added for the 20 version. So either open the themes on the 21 version, press yes that you want to regenerate, take new snapshots, and redeploy these, or use this command on a Process Server environment
https://www.ibm.com/docs/en/baw/19.x?topic=scripting-bpmregentheme
What stopped working for us were:
Cant see validation errors for components
Cant see remove row-buttons from tables
Cant see hover-tooltips for components
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Johan Andersson
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