The button next to the file preview's close icon was Copy Content, whose
overlapping-pages glyph reads as a pop-out control - and for a PDF or any
media/binary preview it was completely dead: those branches never fill
filePreviewContent, so the click hit an empty-content guard and did nothing,
with no feedback.
There is now a real detach button that opens the previewed file in a browser
tab (raw route for PDFs/images/media/text, the server-converted PDF preview
for docx/pptx), severs window.opener by hand so a blocked pop-up stays
detectable, closes the overlay on success (which also stops any playing
media), and disarms on close so it can never open a stale file. The copy
button now toasts 'Nothing to copy in this preview' instead of staying
silent.
Verified live with Playwright against an isolated instance: button visible
and armed on a PDF preview, file-raw answers 200, clicking opens the URL and
tears the overlay down, text previews keep a working copy buffer.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>