The action links of the Scheduler UI are computed like this:
I do not know the logic that led to this decision, but with the addition of
XWIKI-6908 in 7.0M1, those links will be handled as external links and an icon will be displayed next to them, which is not really nice.
We need to fix that.
We could either stop using getExternalURL (if possible) or override the CSS added by
XWIKI-6908 inside the Scheduler app (where applicable).