{"version":"2.1.269","anchor":"decstbm-terminal-renderer-gate-check-rewired-same-flag-dif","canonical_anchor":"decstbm-terminal-renderer-gate-check-rewired-same-flag-dif","heading":"decstbm terminal renderer gate check rewired (same flag, different guard functions)","tier":"internal","area":"Terminal UI","scope":null,"heads_up":null,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.269\/e\/decstbm-terminal-renderer-gate-check-rewired-same-flag-dif","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.269","markdown":"### decstbm terminal renderer gate check rewired (same flag, different guard functions)\n\nThe check that enables scroll-region terminal rendering (DECSTBM) was rewired to new guard functions\n\n**Unclear.** The new guard functions are unnamed beyond minified identifiers, so what they specifically check is not established; nothing has been read yet about the `tengu_marlin_porch` gate for this release.\n\n**What**\n\nClaude Code can use a terminal feature called DECSTBM (a way of scrolling only part of the screen, used to make rendering smoother) when the terminal supports it. The sequence of checks that decides whether to turn this on was changed: the previous set of checks was replaced with two new guard functions, before falling through to the same `CLAUDE_CODE_DECSTBM` environment variable and the same underlying experiment flag as before.\n\n**Why**\n\nThe replacement checks appear to serve the same gating purpose as the old ones, so this looks like an internal restructuring rather than a change in behavior, though what exactly the new guard functions test isn't identified.\n\n- Flag `tengu_marlin_porch`: Not enough to say (read for one account on one subscription tier against v2.1.269; this account: no value returned, anonymous baseline: no value returned, compiled default: off)\n- Area: Terminal UI\n- Names: `CLAUDE_CODE_DECSTBM`\n- Tier: Under the hood\n- Useful: 1\/5\n- Signal: 1\/5"}