Background blur/fade sliders greyed out unless "Use Game Background Images" is checked

[RetroFrogg]

Under Options / Visuals / Backgrounds, there are 2 sliders - “Background Blur Amount” and “Background Fade Amount”. These are only active when the “Use Game Background Images” is checked. However, they still seem to apply when this box is unchecked. For example, when I have that box unchecked, and select a default custom background image, the fade/blur settings are still applied - despite being greyed out and therefore unadjustable. If I check the box again, alter the sliders, then uncheck the box, then the new slider settings are applied to the custom image.

[RetroFrogg]

Also, there seems to be a blur applied to the custom background image even if both of these sliders are set to 0.

[RetroFrogg]

Solved the issue - it was theme-related. Apologies, can't seem to delete this issue.