Build/Test Tools: Swap RTL arrow icons that carry alternative text

[itzmekhokan]

In RTL admin screens some dashicons arrows point the wrong way, with the old-browser fallback flipped correctly and the modern value not flipped.

The swap-dashicons-left-right-arrows rtlcss plugin in Gruntfile.js compares each content value against the six arrow glyphs by exact string equality, so a declaration written with alternative text, as in content: "\f141" / '';, never matches. This sets the alternative text aside before the comparison and restores it afterwards.

Seventeen declarations across seven generated stylesheets change, including the toolbar submenu arrows named in the ticket.

Trac ticket: https://core.trac.wordpress.org/ticket/66020

Use of AI Tools

AI assistance: Yes
Tool(s): Claude Code
Model(s): Claude Opus 5
Used for: diagnosing the rtlcss value comparison and drafting the Gruntfile change. All changes were reviewed and validated by me.

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