Wer lesen kann ist klar im Vorteil... :oops: Tete selbst bietet die Lösung an. Sollte also noch jemand dieses Problem haben:
"I can't set tete009 build as default browser"
Please try the following.
1. Get "helper.exe" file from the "uninstall" folder of official build.
2. Make a new folder named "uninstall" in tete009 build's root folder and put "helper.exe" in that folder.
3. Run the helper.exe with /postupdate option. If you don't succeed, please run the helper.exe as administrator.
4. Run tete009 build and set it as default browser using the same procedure as an official build.