Restore desktop Chrome PWA button

[realchrislovett]

It looks like with the last update, the PWA install button in Chrome-based browsers no longer appears. Adding the start_url line resolves this and restores that functionality. This change also retains the PWA functionality we expect on mobile devices, as tested on my iPhone.

[realchrislovett]

For context, this documentation states start_url is required for PWA functionality on Chromium-based browsers, along with:

name or short_name
icons must contain a 192px and a 512px icon
display and/or display_override
prefer_related_applications must be false or not present

[schlagmichdoch]

Too bad, sorry for the inconvenience! Thanks for pointing it out.
I will release a new patch version tomorrow!

We should use "start_url": "./" though as discussed over here: #329

[schlagmichdoch]

Use "./" instead of "/"

[realchrislovett]

I went with / after reading the Best Practices section of the documentation:

If your app's main page is at the root of your site, you can set the start_url to /.

I see in the issue that caused a problem with using sublocations and PWA installs. I've tested this and ./ indeed solves that problem as well as allows Chromium browsers to show the PWA button. I'll fix my pull request.

[schlagmichdoch]

If your app's main page is at the root of your site, you can set the start_url to /.

That’s the case for https://pairdrop.net/ but might not be the case if the instance is hosted on a subpath like https://example.com/pairdrop/
In this case a start_url of / would lead the PWA to open https://example.com/ which would be wrong.

./ would lead to the path under which the manifest.json is hosted, which is what we want. This is actually also what the documentation says to be the default.

If start_url is unspecified or the value is invalid […], the URL of the page that links to the manifest is used.

Apparently, this leads to the breaking of the installation request, though. They should make that clearer I think.