Optional most-recently-used order for thread.next / thread.previous (or an Alt+Tab-style recent-thread switcher)

[andybergon]

Area
apps/web

Problem or use case
thread.next and thread.previous step through threads in the sidebar's positional order (pinned, then active, then snoozed, then settled), not the order threads were last visited. When I bounce between two threads that sit far apart in that list, "previous" does not take me back to the one I was just on. It walks the list instead, so returning to my last thread can take several presses.

This is the ordering the request in #6966 explicitly left for later ("MRU ordering could be considered separately", "a lightweight recent-thread switcher/preview" as a follow-up). Filing it separately so that follow-up has a home.

Proposed behavior
Offer a most-recently-used traversal option alongside the existing positional prev/next, so both orderings are available. Either shape works:

• a separate pair of bindable commands for MRU previous/next, or
• an Alt+Tab-style overlay that cycles recently visited threads while a modifier is held, similar to editor and browser tab switching.

The positional prev/next should stay as-is; this is an addition, not a replacement.

Why this matters
Switching between the two or three threads you are actively working is the common case, and MRU order matches how tab switching works in editors and browsers. Positional order is better for scanning the whole list; MRU is better for "flip back to what I was just doing."

Related

• [Feature]: Allow Ctrl+Tab keybindings for next and previous thread #6966 requests Ctrl+Tab for the existing positional prev/next and defers MRU as separate.
• Add browser-style tab bar for working across multiple T3 Code sessions #7341 proposes a browser-style tab bar for working across sessions (a visible-UI take on the same multi-thread workflow).

[Williawar]

Opened #11072 with the smallest version of this: a thread.cycleRecent command, ctrl+tab by default. One press goes to the last viewed thread; holding the modifier and pressing again steps further back, release commits (Arc/Dia/Chrome tab cycling). Session-only list, no overlay, no persistence. thread.previous and thread.next are unchanged.