Microsoft is working with Google on a new change that will improve the experience of Chrome-based web apps. After the feature is added to Chromium, PWAs will be restored properly and the operating system will remember their state even when Chrome is restarted/relaunched due to update or crash.
“Session state currently only includes tabbed windows, not PWAs. This must change. In some circumstances, PWAs must be restored on browser restart. But PWA session state must be kept logically separate from tabbed window session state, to help maintain the illusion that PWAs are like native apps rather than part of the browser,” Microsoft explained the idea in a document.
This change will restore web apps via the ‘browser session restore system’. Restoration will work in this way:
- When PWAs are restored attributes normally tracked for browser windows will be tracked and restored (e.g. window position, screen, dimension etc).
- Opening a PWAs directly should not trigger restores like normal windows do. (For example, opening a Twitter PWA should do just that and nothing else; don’t restore PWAs, don’t open the browser (except on macOS where there are some limitations).
- Opening a browser directly should behave as it does today – and still should not restore PWAs in most cases.
On Windows and Linux, Microsoft noted that the normal browser restoration and PWA restoration should not impact each other. The restore data-structure is flexible enough to support additional fields such as the web app’s window positioning or display-mode.
This approach extends browser session restore to store PWA and tabbed browser sessions in separate files. A restore can restore both kinds of sessions – only browser tabbed sessions or only PWA sessions.
“The separation between browser session and app session is not an illusion – it would be actually implemented that way. Closing and opening PWAs will never impact browser session,” Microsoft noted.
Microsoft is planning to introduce these PWAs improvements with Chromium 91 for all operating systems.