Problem when passing from Loki datasource to mixed

Hello
In a dashboard, I configure some queries using Loki (and boom table plugin) as datasource. The 3 queries work fine and appear well in a table.
Problem is I want to add a prometheus datasource.
So, I change Loki Datasource to Mixed Datasource. After doing this, only one column - out of the 3 I should get from loki queries - is displayed alongside the one dedicated to prometheus data. The loki column that appears is randomnly chosen out of the 3. The two others are hidden.
Could you help me understand this bug ?

I am using grafana 8.2.3 and loki version is 2.3.0.