The German word "bearbeiten/Bearbeitung/Bearbeiter" is used for at least three different English words ("assign","progress","edit") in the left sidebar of an issue's page, causing confusion:

"Assignee: <name>" is translated as "Bearbeiter: <name>"

"Start Progress" is translated as "Bearbeitung starten"
"Stop Progress" is translated as "Bearbeitung beenden"

"Edit this issue" is translated as "Bearbeiten dieses Vorgangs"

Traditionally, "bearbeiten" is the translation for "edit". "Assign this issue" is correctly translated as "Zuweisen dieses Vorgangs", and on the user profile page, "assigned" and "in progress" are translated as "zugewiesen" and "in Arbeit", respectively.

So the following translations would make sense in the sidebar:

"Assignee: <name>" --> "Zugewiesen an: <name>" (literally "Assigned to: <name>") (This would also get rid of the exclusively masculine form, by the way.)

"Start Progress" --> "Arbeit aufnehmen" (or "Arbeit beginnen", but not "starten", which is a bit of an anglicism)
"Stop Progress" --> "Arbeit beenden"

"Edit this issue" --> "Bearbeiten dieses Vorgangs" (as before)