more error checking

Fix Bug on export with new Shotcut v23.05.07 #1442

Merge remote-tracking branch 'mlt/master' into threaded_avformat_prod…

…ucer_merged

version 7.2.0

add v7.0.1 release notes

fix underlinking iconv in gdk on macos

fix crash in avformat producer on network URL

version 6.26.0

version 6.24.0

version 6.22.1