@Hasan-aga, there are changes within the following PR fix(modal and dialogues): fixes as per specifications by jbocce · Pull Request #3438 · OHIF/Viewers · GitHub that might help. You can simply try the pertinent changes by updating your platform\viewer\public\config\local_orthanc.js file - in particular the bulkDataURI configuration on about line 35 should be…
bulkDataURI: {
enabled: true,
},
Now this said, instead of running yarn dev:orthanc try running your OHIF dev server pointing to your local orthanc with something like the following from a command prompt…
set APP_CONFIG=config/local_orthanc.js
yarn start
Hope this helps.