vte: guard case 'm' (SGR) against CSI_GT prefix#29
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kdj0c merged 1 commit intokmscon:mainfrom Mar 12, 2026
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Fish 4.x (and other terminals using modifyOtherKeys/XTMODKEYS) send \033[>4;1m at every prompt to enable the keyboard protocol. The '>' prefix sets the CSI_GT flag, marking this as a private/DEC sequence — not an SGR attribute sequence. do_csi() dispatches case 'm': directly to csi_attribute() without checking CSI_GT, so \033[>4;1m is misinterpreted as SGR 4;1 (underline + bold). This causes blank terminal cells to render as '_'. The adjacent case 'p': already has the correct CSI_GT guard; apply the same pattern to case 'm':.
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Tested with fish, those strange underlines are now gone! |
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Problem
Fish 4.x (and other terminals implementing modifyOtherKeys/XTMODKEYS) send
\033[>4;1mat every prompt to enable the keyboard protocol. The>prefix sets theCSI_GTflag, indicating this is a private/DEC sequence — not an SGR attribute.do_csi()dispatchescase 'm':directly tocsi_attribute()without checkingCSI_GT, so\033[>4;1mis misinterpreted as SGR 4;1 (underline + bold). The result: blank terminal cells render as_.This is reproducible with fish 4.x inside any kmscon/libtsm terminal.
Fix
Add the same
CSI_GTguard thatcase 'p':already has, one case below:References
\033[>4;1m(XTMODKEYS enable) at every readline re-entry, not just startupcase 'p':in the same switch already correctly guards againstCSI_GTCSI > Ps m— Set/reset key modifier options