update! Thank you for considering more light themes.
I checked the popup size again and it looks like even though the font size is changed the size of popup didn't actually change as much as I thought. Sorry for the confusion! You can change it back to previous bigger font size if you want (in fact I think I'm in favor of your bigger font change now too as it did make titles/text a lot easier to read). Ability to change font size for the popup in settings page could be a good addition. Thanks again for the splendid addon!
Thanks for the feedback! We'll adjust the popup text sizes and are working on a new theme. Setting for the font-size is a good idea and could be implemented. Expect to see improvements also to view mode 2 very soon.
Edit: Feedbro 3.41.2 (just released) has a new theme called "Chill". It's light but less bright than the "Light" theme.