Upgrade to KML2.3

[dennisguse]

Export format is now KML2.3.
The importer supports KML2.2 and KML2.3.

Tested with:

• OpenLayers (not supported as of 7.1.0): Support for KML2.3 openlayers/openlayers#14104
• GoldenChetah (cannot import KML2.2 or KML2.3) Import from OpenTracks (KML) is unsuccessful GoldenCheetah/GoldenCheetah#4271
• OsmAnd (not supported; supports KML2.2); actually does not have proper KML support; they use XML transformation to GPX Importing GPX/KML ignores timestamps with timeoffset osmandapp/OsmAnd#15271
• OrganicMaps (not supported: supports KML 2.2)
• GpxPod (only supports 2.3)
• Google Maps (not supported; supports KML2.2)
• https://www.gpsvisualizer.com (supported) (not supported; supports KML2.2): informed by email

[dennisguse]

@pstorch Does this work for you?

[pstorch]

I tried it with two web kml viewer (one of them was google maps). And they cannot read the files.
I could open a few files with a Map Viewer plugin in Visual Studio Code.
Didn't see any error logs or so. I try to analyze further.

Edit:
Also Osmand and Locus can't open the files.

[dennisguse]

I just tested with OpenLayers and there it works...

[pstorch]

Hmm, looks like the support for KML 2.3 is not that widespread.

[dennisguse]

:/

Thanks for testing.
I had hoped that support would be more widespread.
I guess, we then have to do some more communication - at least to the open-source projects out there.

[dennisguse]

GPXPod does not support KML2.2, but only KML2.3 https://github.com/eneiluj/gpxpod#known-issues

[dennisguse]

@pstorch last weekend, I had some time check the KML2.3 support out there.
And to be honest - it was worse than expected.
I now see, why people are sticking with GPX ;)

Anyhow....
My proposal: switch to KML2.3 as export format while allowing to import KML2.2.
In addition, we keep pushing open-source projects to slowly migrate as well.
Finally, we add a "compatibility matrix" to our README showing which format to use when.

Does this sounds reasonable?

[pstorch]

I don't know how many users rely on KML 2.2 as a transfer format into another app.
I use KML export only as backup for OT. So for me it's fine 😉

And there is also GPX which is widely supported by other apps.