Hi dolapobabs,
We understand that your 13" MacBook Pro display is flickering when it's disconnected from the TV display, and we're happy to help out. The issue not happening in safe mode also tells us that there's a setting or application within the main user account that is likely causing the problem. When you first connected the TV to the MacBook Pro, do you remember installing any additional display profiles from the TV manufacturer? If not, what do you see in System Preferences > Display > Color > Display Profiles when the TV is disconnected? The resource included below may help as well.
Get help with video issues on external displays connected to your Mac
In particular, does the behavior change at all if you adjust the resolution on the MacBook Pro display?
Please let us know what you find.
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