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+---
+"roo-cline": patch
+---
+
+apply_diff: detect a malformed `-------` separator in the SEARCH section (e.g. `-------import { ... }` with no trailing newline) and surface a clear "Malformed separator" error instead of the generic "63% similar" mismatch. Smaller models that occasionally emit this shape can now self-correct on the next attempt instead of looping. Closes #12210.