When you view an image file, Crop Image (CmdCropImage) and Resize Image (CmdResizeImage) open an editing window. Drag to crop (arrow keys move an edge by 1 pixel) or resize, then save to a new file. The right-click menu has an Image submenu (Copy To Clipboard, Save, Crop, Resize), which also works for images inside PDFs and other documents.
Save images as PNG, JPEG, BMP, GIF, TIFF or WebP
The image save window has a format drop-down: PNG, JPEG, BMP, GIF, TIFF, and WebP on Windows 10 and newer.
Paste image from clipboard
Ctrl + V pastes an image from the clipboard: it’s saved as a PNG in the Downloads folder and opened.
Drag & drop images from a browser
Drag an image from a web browser onto the SumatraPDF window. It’s downloaded to the Downloads folder and opened.
Show Errors for problematic PDFs
If MuPDF reported warnings or errors while loading a PDF, the right-click menu has Show Errors to see them.
Deleting a file cleans up history
CmdDeleteFile also removes the file from history and deletes its home page thumbnail.
Tab and annotation visual tweaks
The tab close button has a round hover background. The selected annotation is marked in blue instead of gray, so it’s easier to see.