Hey-- I was helping someone use Rarebit for their neocities/webcomic. They wound up into an infinite loop complaining that the site was being janky.
cellThumb.innerHTML = `<img alt="${pgTitle}" title="${pgTitle}" src="${pgThumb}" onerror="javascript:this.src='${pgThumbDefault}'"/>`;
Replacing it with a handler that detects this loop (if it errored on pgThumbDefault, dont bother setting the src again) may be the useful enhancement. Perhaps a useful console.error directing the artist to upload a pgThumbDefault.
Btw, awesome wario video-- I coincidentially found that a day before this bug.