That is an instance of the Chrome browser that our launcher uses. Why this is happening for you but not others I'm not sure!
If you start the game from CK3.exe , which bypasses the browser, do you still get this? I'll guess not.
Either way, what antivirus app do you use? You need to make sure all these apps are in its exceptions lists:
ck3.exe (in the Steam CK3-binaries folder)
dowser.exe (in the Steam CK3-launcher folder)
C:/users//AppData/Local/Programs/Paradox Interactive/launcher-v2.2022.14/paradox launcher.exe
C:/users//AppData/Local/Programs/Paradox Interactive/bootstrapper-v2.exe