Patrick Rein uploaded a new version of Network to project The Trunk:
http://source.squeak.org/trunk/Network-pre.227.mcz

==================== Summary ====================

Name: Network-pre.227
Author: pre
Time: 13 October 2018, 2:40:22.865477 pm
UUID: da02cd7c-dbe2-ca43-aff0-4d4fd183876e
Ancestors: Network-tpr.226

Fixes a direct reference to the FileChooserDialog and replaces it with a call to UIManager.

=============== Diff against Network-tpr.226 ===============

Item was changed:
  ----- Method: MailComposition>>addAttachment (in category 'actions') -----
  addAttachment
  
  	self saveFields.
+ 	(UIManager default chooseFileMatching: '*' label: 'Choose attachment') ifNotNil:
- 	(FileChooserDialog openOn: FileDirectory default pattern: nil label: 'Choose attachment') ifNotNil:
  		[:fileName |
  		FileStream readOnlyFileNamed: fileName do: 
  			[:file |
  			file binary.
  			mailMessage
  				addAttachmentFrom: file
  				withName: (FileDirectory localNameFor: fileName)].
  			self changed: #messageText]. !