Use case that reproduces in my environment (Ubuntu + GTK3):
1. Ensure that OpenShift 3 connection is the recent one, by editing it.
2. From main Eclipse menu call File->New->New OpenShift Application.
Wizard should open on Sign-In page with recent OpenShift 3 connection.
Without PR 'Advanced' button is cropped, with PR it is fully visible.

Second use case is:
1. Ensure that OpenShift 3 connection is the recent one, by editing it in OpenShift Explorer.
2. In Servers view call 'New->Server->OpenShift 3 Server Adapter'
Wizard should open on Sign-In page with recent OpenShift 3 connection.
Without PR 'Advanced' button is cropped, with PR it is fully visible.