cubicweb #2356261 css do not load correctly through ajax [validation pending]

No there in any browser.

Also IE notifies (in its status bar) that there is 1 remaining item and then it gets stuck.

priorityimportant
typebug
done in3.15.1
load0.500
load left0.000
closed by#09432a572a44 [IE] use document.createStyleSheet to add CSS dynamically (closes #2356261)