Option to fade non-matching topics when filtering HTML5 exported maps
In addition to the great proposals from Pieter for improvements to HTML5 map export and filtering, I would to suggest the above.
At the moment you have options to show, fade or hide topics that match the filter criteria. However, unless I've missed it, there isn't an option to show matching topics while fading rather than hiding non-matching topics.
This is something you can do with a normal unexported map; the same thing should be possible in an HTML5 map with the addition of a Fade/Hide Non-Matching Topics option to the filter menu.