About the challenge:
The target is to pop an alert() on this host
Tested on Chrome 80.0.3987.163
No user interaction allowed
Lets imagine that all this pages has 'X-FRAME-OPTIONS: SAMEORIGIN' header and well-configured CSP :) So the solution is a link to this page, which triggers the alert, nothing more.
Solved by:
@insertScript unintended(fixed), intended
@SecurityMB intended
@fransrosen unintended x2(fixed & new rule about iframes), intended
@S1r1u5_ intended
@shafigullin intended
Solved? DM me here