Now that Qt is basically no longer OpenSource given there is no LTS and the "community" is barred from choosing direction or maintaining its own LTS, a port of Scintilla was needed. Ls-Cs is a port of CopperSpice which is a port of the last real OpenSource version of Qt, version 4.8. LsCsScintilla is a port of Scintilla to work with Ls-Cs.
All Qt+Scintilla based editors should be able to port to Ls-Cs+LsCsScintilla rather painlessly.
RedDiamond uses Ls-Cs+LsCsScintilla
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