I had a real hard time debugging and cleaning my translation tables.
The root cause turned out to be the t()'s in the feature file.
Imho they should not be there as
* for the default textgroup they come from other modules where the t() already is, so are not necessary
* for other textgroups they do real harm, causing a second DB entry like this:
** somefieldname, textgroup=field, context=field:foo:title # good entry
** somefieldname, textgroup=default, context=field:foo:title # evil entry
2.0
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