X_UI_QR_CAPACITY
Means
text is too long for a QR code this component can draw
Typical cause
<QrCode value> is more UTF-8 bytes than version 3 at error-correction level M holds — 42. @ultimat3/ui encodes versions 1–3 only (21×21 to 29×29 modules): the versions with at most one alignment pattern, no version-information block and one Reed-Solomon block, which is what keeps the encoder a dependency-free page rather than a library. A short URL (origin + '/' + 6-char slug) runs 25–30 bytes and fits; a full page URL does not. Refused rather than truncated, because a truncated link scans and then leads nowhere; the cause names the byte count and the ceiling
Fix
shorten the value (a short URL, not a full page URL), or draw it with a full-range QR library outside @ultimat3/ui