Use external tools like ImageMagick or XnConvert to batch convert your .webp files to .png before importing them into ThumbsPlus. 3. Use External Viewers
Because WebP is a relatively newer format compared to the legacy formats ThumbsPlus was built to handle, integration sometimes requires specific updates or workarounds. Support WebP — Плагин для WordPress thumbsplus webp
to batch-process them into JPEG or PNG files that the older software can recognize. Google for Developers Managing WebP with ThumbsPlus Use external tools like ImageMagick or XnConvert to
If you are running an older version of ThumbsPlus (v7, v8, or v9), you will likely encounter a "Unknown file format" error when trying to open a WebP image. The format simply did not exist in the mainstream when those versions were architected. Look at the list of file types
Look at the list of file types. You need to add *.webp to the list of image files so the app knows to scan them. 3. Check for Plugins
As of the latest widely available information (including updates through 2026), . While ThumbsPlus is a robust image management and cataloging tool for Windows, its ability to render WebP files depends entirely on the version and the underlying system codecs.