This is a chat room. If you do not have Mesh, hold down shift while clicking the top of the r in the SCRATCH logo. Click Turn fill screen off, click the white space, hit open, browser, Scratch-UI-Panes, ScratchFrameMorph, menu/button actions, addServerCommandsTo:, then change t2 < true to t2 < false. Click the browser, hit accept. Shift-click-r, then click save image for end-user, then yes. Scratch will close, but you then have Mesh. Shift-click Share next to edit and help and you see Host Mesh and Join Mesh. You're done!