How to avoid escaping custom Grafana variable?

Question

My Grafana dashboard shows statistics for some Elastic documents. Some of these documents have the attribute important_details, some don't. I want to create a "Has important details: Yes/No/All" filter.

What I did was I created a new has_important_details variable, type "Custom", with the following options:

Yes : _exists_:important_details, No : NOT _exists_:important_details

Then, I'm editing the panel and add $has_important_details to the Query field.

This doesn't work, and the reason seems to be that instead of _exists_:important_details, it actually sends the query

_exists_\\:important_details

and likewise

NOT\\ _exists_\\:important_details

for the opposite.

Answer 1

I found it out myself after all. Instead of $has_important_details, the Query field should be ${has_important_details:raw}.