Assets panel doesn’t accept images with „.tif“ extension

[mac_heibu 416]

Bug: If one drags a ".tif“ image directly from the Mac desktop into the „Assets“ panel, it will not be accepted. „.tiff“ (double f) is working fine. Both files can be dragged onto Publisher’s canvas without issues. 

(macOS 10.14.5., Affinity Publisher 1.7.1.399 and former)