I was able to reproduce with the following steps:
1. Go to Developer Perspective
2. Click +Add -> From Git
3. Create a sample Node.js application with all of the defaults
4. Go to the Deployment details page and add a reference to any config map from the Environment tab
5. Click Actions -> Edit node-js-ex
6. Add a CPU request of 100 millicores (probably any edit will work), then click Save
7. Go back to the Deployment details, Environment tab
The config map added in step (4) is missing.
Moving to the Dev Console team since they maintain this editor.
Created attachment 1759885 [details]
Edit Application action doesn't overwrites Deployment envFrom values on save
Verified on build version: 4.8.0-0.nightly-2021-02-26-221801
Browser version: Chrome 84
KCS article written about this bug: https://access.redhat.com/solutions/5857191
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory (Moderate: OpenShift Container Platform 4.8.2 bug fix and security update), and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.