I’m also having the issue with no fix as of yet. This is the second time this has happened after I uninstalled the app the first time around. I noticed when I turn on block scripts it stops inverting the page. Which means it is an issue with the app itself. I also do not have classic or smart invert colors enabled on my iphone. I have also turned off dark mode and it has not fixed the problem. As stated above the inverted webpages go away when I block scripts so it is 100 percent a bug in the app itself. Please fix this bug as soon as possible.