Local save data does not work in some situations

[FormularSumo]

Testing out indexedDB data storage - persistent storage permission requested or not

Desktop (Linux/Windows)

Chrome/Firefox

Data saves perfectly, whether reloading the page, browser, or web app

Gnome Web

Data persists when reloading the page. But when restarting the browser or installed web app, only uses data from last time you reloaded. Which can mean old data is used or no data, it's bizarre. Tested with tracking protection on and off.

Android

Chrome/Firefox

Same as Gnome Web desktop, including web apps (regardless of whether browser/tab is open)

ChromeOS

Same as above. Note: seems like only Chrome can install web apps, so unsure about them in other browsers

iOS

Data does not persist ever, regardless of browser, tracking protection, in-browser vs web app, reloading.......

[FormularSumo]

According to this extension - https://apps.apple.com/gb/app/web-inspector/id1584825745 - nothing is saved in local storage on iOS. Doesn’t show indexedDB though.

According to Safari storage in settings 156 MB is used by the site - suggesting both local storage and indexedDB are being used