cubicweb #1624851 display splash image while facets are reloading content [resolved]

to make it easier for the user to realize he has to wait before clicking again

prioritynormal
typeenhancement
done in3.13.0
load0.500
load left0.000
closed by#f2dbac46031e [facets] display splash image while facets are reloading content (closes #1624851)