Personally I’d count kanji as ‘learned’ way before being burned, though sometimes i forget burned items after a while. Other scripts count Guru as learned.
Also, you already have the burned information in the SRS breakup bar, which also has a hover to see kanji/vocab etc.
But still, I agree this would be nice, with a total (/8995) and percentage shown.
I made a similar script for myself, Show Number Of Learned Kanji/Vocab.
You can edit the settings to define what you’ve ‘learned’ as Burned, though the default is Guru+.
Javascript really isn’t all that bad as long as you’re in control of it.
For example, i love that hashmaps are a basic part of the language (=Object).
That way, instant lookups (O(1)) are simple syntactically and don’t need imports.
Example
const hashmap = { "日": object1, "月": object2 };
const myKanji = hashmap["月"]; // O(1), aka constant time lookup. which is of course more relevant for bigger maps/lists