Dunst can be set to transparent in the config but this sets the whole window transparent. Many applications are able to use rgba-color-values to display colors accordingly. This has the advantage of being able to display the text non-transparent and the background transparently. That improves readability (vs. everything is transparent).
Would be awesome, also, if we could set an separator to transparent, so we can have multiple and separeted notifications, something like that:

Would this also let us have non-transparent icons/images while having tranpsarent notifications?
That would be a really nice feature!
Implemented with #717, now all color strings support transparency.
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Would this also let us have non-transparent icons/images while having tranpsarent notifications?
That would be a really nice feature!