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I want to turn on accessibility permission to Greenify app. But I'm unable to click "ok". I also have Twilight and since some security built in the system, I have to disable, stop or uninstall the aforementioned app which uses an screen overlay to adjust color temperature at sunset and sunrise.
Thing is that I'm still unable to click the ok button. I believe some other app is using some screen overlay but I don't know which one.
How can I find out? Other that trial and error uninstalling and reinstalling every app and their combination (in case there are more than one).
P. S. Already found it, was Nav Layer. Anyway, I keep the question for research.