RegEx capture groups issue

Some of my capture groups result in empty `span.color` classes. I made edits to the regular expressions but then they resulted in some characters not being output to the DOM. Any help here would be appreciated.

Start by reproducing the capture-group case that creates empty span.color classes and compare the generated DOM with the expected output. Trace the regular-expression handling to identify why edited expressions omit characters, then verify that capture groups produce neither empty color spans nor missing DOM text.

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