Can't add a COGS webhook (1.2)

Hi! I’m running gitea 1.2.0+rc3-5-g73ad7d2. Whenever I want to add a COGS webhook (I want to talk to my Taiga instance), I fill in the form, then press the save button, then get a blank page with no information whatsoever. The source code of that page just contains

 inside the .

It should be fixed in latest release