PreviewJob uses ThumbCreator, which uses QWidgets to do the plugin specific configuration. Currently, it opens a dialog on a configuration request and expects the same dialog passed in again (as QWidget*) to apply/save a configuration change.

This has several drawbacks:

• All plugins link to QWidgets, even when having no configuration options
• All previewjob users link to QWidgets, even when not exposing any means to invoke the configuration dialog

PreviewJob uses ThumbCreator, which uses QWidgets to do the plugin specific configuration.

That is solved in T14695

https://invent.kde.org/frameworks/kio/-/merge_requests/1137