Firefox 158 PWA “Installation Incomplete” Error: What to Update
Firefox updated cleanly, and now your PWAsForFirefox web apps stop at “The installation seems to be incomplete.” Which piece is out of date?
- PWAsForFirefox 2.20.1 fixes web apps crashing at launch with Firefox 158.
- Keep the extension and native program in sync; the native program does not update itself.
- If the failure persists, reinstall the runtime and then patch profiles and runtime from the extension settings.
Check the compatibility release before blaming the disk
If a web app installed through PWAsForFirefox stopped launching after Firefox 158 and reports “The installation seems to be incomplete.”, check that PWAsForFirefox is on 2.20.1 or later. The project’s October 9 release explicitly fixes launch crashes with 158 and asked users to update before Firefox’s October 13 release.
Mozilla lists the same issue in Firefox 158’s release notes. An error that sounds like damaged installation files can therefore point to a known compatibility mismatch in this particular setup.
Updating the browser does not update every part of PWAsForFirefox
The project combines an extension, a native program and an app runtime. Treat them as separate components when checking the installation.
| Component | Role | Check |
|---|---|---|
| Browser extension | Provides the interface for apps and profiles. | Its version should match the native program. |
| Native program | Manages and launches web apps on the operating system. | Update to 2.20.1 or later. |
| App Firefox runtime | Runs the standalone app windows. | Apply the compatible runtime and profile patches. |
The official update guide says the native program cannot automatically update itself. Update it manually or through the supported package manager used for installation. The extension can notify you when it detects an outdated native component, and package repositories can lag behind upstream releases.
That gap appeared in an October 17 Manjaro forum report: the user had Firefox 158 but firefoxpwa 2.19.0 on the stable branch, and several apps failed. Those are the versions reported at the time; inspect your repository’s current package rather than assuming it still has that mismatch.
If updating is not enough, reinstall first and patch second
Mozilla’s follow-up sequence is Reinstall runtime → Patch profiles and runtime, in the extension settings.
- Bring the extension and native program to matching versions, 2.20.1 or newer.
- Retry the affected app.
- If the error persists, select Reinstall runtime.
- Then select Patch profiles and runtime and retry.
According to the extension guide, reinstalling replaces the app runtime with a fresh Mozilla download without removing profiles or data or changing your main Firefox browser. It does replace a manually installed custom runtime. Platforms without automatic runtime installation support need a manual installation.
The patch command applies the installed patches to profiles and runtime. Update web apps is a different operation: it refreshes manifests and operating-system registrations. It does not substitute for the specified patch step.
A failure in the main Firefox browser needs a different diagnosis
This fix concerns desktop apps launched through PWAsForFirefox. It is not a fix for a missing mobile home-screen option or a website’s install banner.
If the main Windows Firefox installation also fails to start, use Mozilla’s general installation-error guidance, which covers installation files and disk problems. Identify whether the app runtime or the main browser is failing before removing profiles or reinstalling the whole browser.