• Lua regex.find, regex.match, expect_regex and on(…, 'regex') now accept PCRE features (lookahead, lookbehind, back-references, inline flags) as SyncTERM-Lua does. lordbot.lua and twbot.lua stopped with a “bad regex” error.

• Windows version: installer (per user, Start menu shortcut, uninstaller) and a portable zip. Built-in SSH, scripting (Python and Lua), Telnet, RLogin, serial (COM ports), local shells (PowerShell or cmd) and Zmodem work on Windows; credential passwords use Windows Credential Manager.
• Built-in Zmodem (ported from Lantern Terminal's engine), used on Linux and Windows. Downloads still start by themselves; uploads start when the host is ready to receive.
• A program icon of its own (taskbar, window list, menus, the Windows exe and installer).

• Each tab now has its close button inside it (middle-click also closes a tab).

• Lua scripts did not have the standard debug library (SyncTERM-Lua and Lantern scripts may use it).
• High CPU use: the built-in SSH engine busy-waited for data, and the window redrew itself continuously. An idle window now uses almost no CPU.
• Scripts could connect to the session's port instead of the application when a session had a port number set (the variable names clashed).

1.3.1 is the first public release. Earlier builds were private test versions.