This Add-on provides the following features:

Categorize songs using colors to e.g. highlight your collection, display song status or apply quality measures. Visible in search results and on the song detail page.
Share categories by loading from JSON raw file hosted on your favorit cloud platform like Github (https://raw.githubusercontent.com/...) or Dropbox (https://dl.dropboxusercontent.com/...)
Display song IDs and Covers while browsing Search Results
Display Metatags from USDBSyncer while browsing Search Results
Listen into song samples while browsing Search Results
Use on Smartphones (with "Firefox Nightly" App)
Disable accidential redirects by touching search result rows on mobile browsers

examples for colorizable categories:

(the original intention) display the status of songs "done" (=download and play), "todo" (=songs I want to checkout next), "challenging" (=songs that require a higher degree of effort to make them playable and are currently broken in some way)
divide workload between friends with a category per friend
display a quality measure with categories like "video missing", "bad audio", "wrong GAP", etc.

Examples for the JSON configuration file structure can be found at https://github.com/mjhalwa/usdb_plus/tree/main/examples Note: (at least on Android) this App seems currently only to be supported by the "Firefox Nighly" App

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