[MapProxy] transparent layers get an opaque background after merging

[Tobias Wendorff]

Thanks for your idea, I thought "request_format" is for WMS only.

But it didn't work:

```
  format: image/png
  request_format: image/png
```

This also would work in "caches" only, not in "layers" (where merging is
also allowed).

It really might be a Pillow problem. I'll try to extract the images from
the mbtiles and analyze them.


Am 13.10.2020 um 20:38 schrieb Travis Kirstine:
> You may need to define a request_format: image/png to the cache to
> ensure that the source images are transparent.
>
https://mapproxy.org/docs/latest/configuration.html?highlight=request_format#request-format