Tested on HDRP 7.1.1 / 7.1.5 / 7.1.6 / 7.1.7 / 8.0.1
Can repro on any version from 2019.3+

Simple repro steps is :
- Create a new HDRP project
- Make sure TAA is enabled for scene view (Edit -> Preferences -> HD Render Pipeline -> set Scene View Anti-Aliasing to TAA), and enable "Animated Materials" ("Always Refresh" in 2020.2) in scene view fx toolbar dropdown
- Select any opaque game object and see the outline flicker

Can be reproduced with creating a 3D project and importing HDRP package, or creating HDRP template etc.