@BHAVIN-GUPT Hi. I am the developer of this extension. It might be being used on an invalid site defined by opera such as opera addons, settings, or new tab. You also have to manually change permissions if you want to use it on your search engine for the same reason. Also, if there is a part of a website that the flashlight cannot move to, turn it off while you need to see there. (Spent hours trying to fix that, but it is not by any means a simple fix.)
@erikreegisteel: Sorry, I only just realised the popup doesn't show up on Opera in its full width, and that's what's wrong. For what it's worth, an update to fix this issue is already in the publishing queue (since August, 2024), we will now have to wait for a moderator to verify the changes. Then you should be able to have the on/off switch on all pages. 🙂
The addon moderation process takes a while on Opera, I will reply to your comment again once the update got released.