From ChangeLog: https://sigil-ebook.com/2020/11/21/sigil-1-4-2-critical-fix-release/
Bug Fixes Since Sigil-1.4.0:
* critical bug fix for incorrectly xml encoding of opf metadata attributes that
use entities
* fix bug in "Add Existing" files when file names would require percent
encoding
* fix bug in multiple language spellchecking dialog word lookup when no
language attributes used
* update de, nl, sv, ko, ru translations that missed the Sigil 1.4.0 initial
release
* critical bug fix for over xml encoding html used inside metadata in the opf
* revert ctrl-f to it long standing Find and Replace behaviour
If you are using either Sigil-1.4.0 or Sigil-1.4.1, we strongly urge you to
upgrade to Sigil-1.4.2.
PR: 251322
Submitted by: jonc@chen.org.nz (maintainer)
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