Changed
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* PPMd: Use stream encoder/decoder instead of buffered one.
* PPMd: Use ppmd-cffiv0.3.1 and later.(268)
Added
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* PPMd compression/decompression support.(255)
* New API to set methods to set header encode mode, encode or encrypted.(259)
* Support Python 3.9.(261)
* Support arm64/aarch64 architecture on Linux.(262)
Fixed
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* Append mode cause error when target archive use LZMA2+BCJ.(266)
* Fix zstandard compression/decompression.(258)
Deprecated
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* Drop support for python 3.5 which become end-of-life in Sept. 2020.