Intermittent "internal error" with multiple XIBs in Xcode 26.0 beta 2 (17A5241o)

On several different XIBs I get a compiler error like

Internal error. Please file a bug at feedbackassistant.apple.com and attach "/var/folders/1v/ 516am8h11fzbmdy9sh r1znh0000an/T/|B-adent-diagnostics 2025-06-30 15-02-36 468000" W

These XIBs were unmodified, the only different was the Xcode version they were compiled against. Any suggestions for a fix, workaround, or troubleshooting? I tried restarting Xcode, restarting macOS, cleaning the build, and deleting derived data.

FB18538052

Intermittent "internal error" with multiple XIBs in Xcode 26.0 beta 2 (17A5241o)
 
 
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