I make some test with differents scripts.
First I put away Library Tree, Album list panel and both bios
Spider Monkey Panel v1.4.1 (Musicbrainz: Musicbrainz by marc2003): initialized in 610 ms
Spider Monkey Panel v1.4.1 (Last.fm Similar Artists + User Charts + Recent Tracks: Last.fm Similar Artists + User Charts + Recent Tracks by marc2003): initialized in 49 ms
Spider Monkey Panel v1.4.1 (Last.fm Similar Artists + User Charts + Recent Tracks: Last.fm Similar Artists + User Charts + Recent Tracks by marc2003): initialized in 40 ms
Spider Monkey Panel v1.4.1 (Last.fm Similar Artists + User Charts + Recent Tracks: Last.fm Similar Artists + User Charts + Recent Tracks by marc2003): initialized in 45 ms
User Interface initialized in: 0:01.181741
FFmpeg version: 4.3.1
Loading
foo_enhanced_playcount: loaded
Querying last.fm: http://ws.audioscrobbler.com/2.0/xxxxxxxxxxx
Startup time : 0:04.657253
Then I put a Biography v1.1.3 by WilB
Spider Monkey Panel v1.4.1 (Biography: Biography v1.1.3 by WilB): initialized in 602 ms
Spider Monkey Panel v1.4.1 (Musicbrainz: Musicbrainz by marc2003): initialized in 119 ms
Spider Monkey Panel v1.4.1 (Last.fm Similar Artists + User Charts + Recent Tracks: Last.fm Similar Artists + User Charts + Recent Tracks by marc2003): initialized in 47 ms
Spider Monkey Panel v1.4.1 (Last.fm Similar Artists + User Charts + Recent Tracks: Last.fm Similar Artists + User Charts + Recent Tracks by marc2003): initialized in 44 ms
Spider Monkey Panel v1.4.1 (Last.fm Similar Artists + User Charts + Recent Tracks: Last.fm Similar Artists + User Charts + Recent Tracks by marc2003): initialized in 41 ms
User Interface initialized in: 0:01.419245
Loading
FFmpeg version: 4.3.1
foo_enhanced_playcount: loaded
Querying last.fm: http://ws.audioscrobbler.com/2.0/xxxxxxxxxxxx
Startup time : 0:05.152534
Changing the WilB's bio to Biography, Covers, Albums, Title, Similar artist, Lyrics info.www.last.fm v14042021 by kgena_ua
Spider Monkey Panel v1.4.1 (Biography: Biography, Covers, Albums, Title, Similar artist, Lyrics info.www.last.fm v14042021 by kgena_ua): initialized in 11790 ms
Spider Monkey Panel v1.4.1 (Musicbrainz: Musicbrainz by marc2003): initialized in 127 ms
Spider Monkey Panel v1.4.1 (Last.fm Similar Artists + User Charts + Recent Tracks: Last.fm Similar Artists + User Charts + Recent Tracks by marc2003): initialized in 41 ms
Spider Monkey Panel v1.4.1 (Last.fm Similar Artists + User Charts + Recent Tracks: Last.fm Similar Artists + User Charts + Recent Tracks by marc2003): initialized in 36 ms
Spider Monkey Panel v1.4.1 (Last.fm Similar Artists + User Charts + Recent Tracks: Last.fm Similar Artists + User Charts + Recent Tracks by marc2003): initialized in 39 ms
User Interface initialized in: 0:12.463360
Loading
FFmpeg version: 4.3.1
foo_enhanced_playcount: loaded
Querying last.fm: http://ws.audioscrobbler.com/2.0/xxxxxxxxxx
Startup time : 0:15.990977
The difference with kgna_ua is appreciable.