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Select text data in a browser or in a text editor or file(s) from your system and press Ctrl+C (Cmd+C for Mac OS XmacOS).
Switch to UGENE with an opened project, click the project area and press Ctrl+V (Cmd+V).
The copied data or file(s) will be opened in UGENE.
Another way for the file(s) is drag’n’dropdrag-drop. Using your mouse, drag and drop the files from the file system to UGENE, and they will be opened by the program.