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TEMP vs persistent window — when to use which in JustZix

15 May 2026 · by JustZix Team

JustZix has four types of on-page dev windows. Each one opens in two ways: as a persistent pane tied to a rule, or as an ephemeral TEMP pane summoned by a shortcut. The choice is not always obvious — this article gives you a simple decision model.

Two modes of the same window

CSS pane, JS pane, JS Console, Output Console — these are the same four windows regardless of how you open them. Only their lifecycle differs.

Persistent pane — when you use it regularly

A persistent pane is an investment: you create it once, tie it to a URL pattern, and it returns every time you visit a matching page. Pick it when:

• You need the same CSS/JS on every visit to a given page.
• You want the window to survive a reload — e.g. a Web Vitals monitor that logs after every F5.
• You need that configuration on another device (sync).
• You want several windows at once — e.g. two consoles side by side, joined into a snap group.

TEMP pane — when it is a one-off

A TEMP pane is a handheld tool: pull it out, use it, put it back. Pick it when:

• You are on a page you probably will not return to.
• You have one question for the DOM or the console.log and that is it.
• You do not want the change to stay in your configuration or get synced.
• Speed matters — a shortcut beats opening the panel and creating a rule.

Rule of thumb

Ask yourself one question: will I need this after the page reloads?

• No → TEMP. Shortcut, work, reload, clean.
• Yes, once → TEMP is enough for this session.
• Yes, every time I come back here → a persistent pane tied to a URL pattern.

When in doubt, start with TEMP. Promoting up is cheap; cleaning up an unneeded rule is not.

Promoting TEMP into persistent

Caught yourself typing the same TEMP code a third time? Time for a rule:

1. Select and copy the TEMP window's content (a plain Ctrl+C in the editor).
2. Open the extension panel, create a rule with the right URL pattern.
3. Paste the code, enable the window of that type on the rule.
4. Close the TEMP — from now on the window returns on its own.

Pitfalls

• TEMP does not cascade. Persistent windows inherit their enabled state through the folder/group/rule hierarchy. TEMP is flat — it is simply a window that is either there or not.
• Reload is not the same as SPA navigation. In a single-page app, a route change without a reload does not remove a TEMP — only a full reload does.
• Two consoles. Since TEMP gives you max one window per type, make the second console persistent — or make one of the two persistent and the other TEMP.

See also

• TEMP panes — the full write-up on ephemeral windows
• Snap connections — joining persistent windows into groups
• Mini-IDE in a tab — all four window types

Install JustZix — and choose deliberately: ephemeral or persistent.