I managed to get rid of it (I was blocked by this) by clicking the "..." button in the input frame and choosing "Create image" which was prepended to my prompt.
No idea what happened there... I have a valid/paid account, no browser extensions... strange stuff.
I guess that. I have a paid account ($20/month flavor) and have the link saved. I just asked it to create an image of a landscape and it popped up this blocking request to use pyxl.pro