Tcl/Tk 9.1 adds text handling, timers and accessibility features

Tcl/Tk 9.1 adds Unicode normalisation, a monotonic microsecond timer and list filtering to Tcl. Tk gains screen-reader support and initial support for right-to-left text, alongside widget improvements. Embedders also need to check a compatibility requirement: applications must call an initialization routine, while platform-specific path and executable lookup behaviour has changed.

Tcl/Tk project · Sep 29, 2026

Why it matters

Maintainers of scripts and desktop tools have concrete upgrade checks beyond new syntax.

More context

Try the published 9.1.0 source release against an existing application. Test accessibility with your supported screen readers, and review the initialization requirement if your program embeds Tcl.

Keep in mind

The page lists 9.1.0 as the latest release but retains development-era wording. Right-to-left support is explicitly initial; 1min has not tested platform or extension compatibility.

Original read