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Click Preferences thenclick the Browser option, switch back to the client option then click Save.
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Click Back to return to the application catalog and bookmarks page then launch the app of your choice.
Click Open Horizon Client. (Your browser may show this prompt in a different way.)
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Make sure to click Allow when prompted to allow sharing.
If you missed this prompt or need to make changes, right-click on the tray icon and select Sharing (Windows shown, MacOS is similar).
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