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The internal deparser did not add parentheses when necessary, e.g. before ‘[]’ or ‘[[]]’. (Reported by Lukas Stadler; additional fixes included as well).
‘sub()’ and ‘gsub()’ did not handle regular expressions like ‘"\s{2,}"’ properly if the text contained ‘NA’ or non-ASCII elements in a UTF-8 locale. Part of this was due to a bug in the TRE library. (PR#16009)