- update to 9.1.0:
* Fix loading FriBiDi on Alpine #6165
* Added setting for converting GIF P frames to RGB #6150
* Allow 1 mode images to be inverted #6034
* Raise ValueError when trying to save empty JPEG #6159
* Always save TIFF with contiguous planar configuration #5973
* Connected discontiguous polygon corners #5980
* Ensure Tkinter hook is activated for getimage() #6032
* Use screencapture arguments to crop on macOS #6152
* Do not mark L mode JPEG as 1 bit in PDF #6151
* Added support for reading I;16R TIFF images #6132
* If an error occurs after creating a file, remove the file #6134
* Fixed calling DisplayViewer or XVViewer without a title #6136
* Retain RGBA transparency when saving multiple GIF frames #6128
* Save additional ICO frames with other bit depths if supplied #6122
* Handle EXIF data truncated to just the header #6124
* Added support for reading BMP images with RLE8 compression #6102
* Support Python distributions where _tkinter is compiled in #6006
* Added support for PPM arbitrary maxval #6119
* Added BigTIFF reading #6097
* When converting, clip I;16 to be unsigned, not signed #6112
* Fixed loading L mode GIF with transparency #6086
* Improved handling of PPM header #5121
* Reset size when seeking away from "Large Thumbnail" MPO frame #6101
* Replace requirements.txt with extras #6072
* Added PyEncoder and support BLP saving #6069
* Handle TGA images with packets that cross scan lines #6087
* Added FITS reading #6056
* Added rawmode argument to Image.getpalette() #6061
* Fixed BUFR, GRIB and HDF5 stub saving #6071