loadOmeTiff with relative path no longer works

[xinaesthete]

Describe the bug
This is fairly trivial, but it used to be possible to call something like loadOmeTiff('/api/image.ome.tiff'). This now throws an exception when it passes that string to new URL(source) (here). I can work around this at my end by being more careful about forming a working string or URL... so now in my client code I have something like this

if (source.startsWith('/')) source = new URL(source, window.location.href)
loadOmeTiff(source)

That's not a totally robust method, but a passable hack for me for now... but it was a breaking change for me when I updated to the latest Viv version, so maybe worth considering (and probably source.startsWith('/') won't catch all potential problems).