Email support@pportal.bid.
How do I add PDFs? Tap + in the list and choose files, or sync a folder from Files (iCloud Drive, Google Drive, OneDrive, Dropbox) or a WebDAV server from the Cloud Sync section of the sidebar.
Search finds nothing in a new PDF. Indexing runs in the background; a spinner shows next to the file until it is done. Scanned pages are read with on-device text recognition and take longer.
A PDF won't import. Password-protected PDFs can't be opened. Remove the password first.
Will my files be changed? No. Highlights and bookmarks are kept in the app, and the PDF itself is never modified.