I have the same problem, a TeamViewer 11 licence and running Ubuntu Linux as my primary OS. Updating to Ubuntu 18.04 broke TeamViewer. I have not found a solution but came up with a workaround - a Windows XP virtual machine running under Virtualbox, using an old leftover XP license key. TeamViewer 11 works just fine this way and XP doesn't take much in the way of resources by today's standards. (I'm using 192MB memory and 5GB disk for my XP virtual machine.) You could run an older version of Linux in a virtual machine instead if you don't have a suitable XP key and disc handy. Obviously it would be preferable to run TeamViewer directly but at least it's functional this way.
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