Support
HEIC variants may be unsupported. Try exporting the source as JPEG first. Animated files become a single frame; TIFF imports its first page. Originals are unchanged.
Using the extension
Image Resizer to PDF is built for desktop Chrome. Click its toolbar icon to open the workspace, add your images and choose your export settings.
Troubleshooting
Try a small PNG or JPEG first. If folder saving is unavailable, use ZIP export. Check the exported file size when an upload service has a KB limit; an exact file size is not guaranteed. Closing the app clears the current queue, so save your exports before closing.