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The performance of ‘grep’, ‘sub’, ‘gsub’ and ‘strsplit’ has been improved, particularly with ‘perl = TRUE’ and ‘fixed = TRUE’. Use of ‘useBytes = TRUE’ for performance reasons should no longer be needed and is discouraged. It may lead to incorrect results and newly also to runtime errors thanks to the previous item.
Use of ‘tools::Rdiff’ for uncompressed PDF files is no longer documented: support may be removed entirely in future.