On platform that doesn't support browser extension (such as Google Chrome Android), you can run YouTube Musical Spectrum [1] using one of these bookmarklets:
javascript:import("https://cdn.jsdelivr.net/npm/@mfcc64/ytms/script.mjs")
javascript:import("https://unpkg.com/@mfcc64/ytms/script.mjs")
[1] https://github.com/mfcc64/youtube-musical-spectrum