Bromium claims to be seamless to end-users, but it's not available to consumers, except on some HP devices, https://www.theregister.co.uk/2017/02/13/hp_bromium_virtuali...

As for practicality, if your daily workflow involves a browser extension that has no replacement, the options are:

  - stop doing the task
  - all browsing with insecure browser, no isolation
  - single task with insecure browser, no isolation
  - single task with insecure browser, some isolation

Most people will do #2 or #3. Those who care about security will do #4, with quality of isolation dependent on their threat model.