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Bookmarks and Tabbed Browsing
To bookmark a set of tabs:
1. Press CtrlCmd+D or select Bookmarks > Bookmark This Page.
2. Check the Bookmark all tabs in a folder checkbox to store all the tabs in the current window into a bookmark folder.
3. To open bookmarks in tabs, open a bookmark folder menu and choose Open in Tabs. You can also middle-click on the folder to open its contents in tabs. The bookmarks will open in existing tabs, not new ones.