Created attachment 370528 [details]
Screenshot of an incompletely expanded window

Gnucash 3.0, German version, on Mac Sierra (10.12.6):

When looking up a customer the "Kunde suchen" ("Search for customer", I guess in the English version) window comes up incomplete and sticking. So does the windows to search for a bill. The buttons at the lower edge are just about visible, their text is visible as 'There's something there, but you can't read it' (about 30 percent of the button I guess, won't count pixels on a retina display :( ). The drop down list buttons for selection of search parameters are stuck, the input box for the search text is accepting text, however. (Screenshot appended)

Workaround:
Once you resize the window the lower edge buttons become visible, the window "pops" to a correct aspect and the selection buttons become operative.

Cheers

J W