I cannot reproduce with the latest 2.2.1 release candidate.
I tried with the release candidate build for macOS from here:
https://github.com/LibreCAD/LibreCAD/releases
tigadad wrote
Version: v2.2.1.2
Compiler: Clang 15.0.0
Compiled on: Jul 14 2025
Qt Version: 5.15.2
Boost Version: 1.88.0
System: macOS 10.15
Editing the text of a vertical dimension does not delete the original and leaves both a a shadow. It does not appear to happen with horizontal dimensions.