Tokenisation that drops the term someone typed, ranking that buries the exact match, and zero results with no way out. The failures a search box hides.
Variable axes, COLR palettes, metrics that disagree, and a deliberately broken checksum. The font cases that break renderers, subsetters and export pipelines.
Turn labels, autocomplete tokens, grouped controls, errors, and keyboard behaviour into explicit form-testing contracts using live demos and editable fixtures.
SVG rendered through an img element runs in secure static mode and refuses every external resource. Here is why exports silently lose type and pictures, how to embed them, and how to test that it worked.