Not sure if this is could be considered a bug - If multiple paragraphs are built with the same builder with `builder.reset()`s in between, only the first paragraph's `unresolvedCodepoints()` call will return results, and any other paragraphs built with the same builder will return an empty list.
Reproduction: https://jsfiddle.net/cexfLsry/2/
Using a fresh builder solves the issue. Removing `builder.reset()` also makes `unresolvedCodepoints()` work, but we need `reset()` to reuse builder for different paragraphs.
We're caching the builders because the creation overhead adds up when rendering large amount of rich text, which can be easily eliminated by simply caching 3 builders of start/center/end align.
Thank you for the detailed explanation, now it makes much more sense to me.
May I ask what are the issues with the reproduction links and how may I correct them?
Thank you!