Fixing Wallaby's "Invalid Session ID" Error

When running Wallaby integration tests in your Phoenix application, you might encounter this cryptic error:

** (EXIT from #PID<0.8921.0>) an exception was raised:
     ** (RuntimeError) invalid session id
         (wallaby 0.30.9) lib/wallaby/httpclient.ex:140: Wallaby.HTTPClient.check_for_response_errors/1
         (wallaby 0.30.9) lib/wallaby/httpclient.ex:56: Wallaby.HTTPClient.make_request/5
         (wallaby 0.30.9) lib/wallaby/webdriver_client.ex:324: Wallaby.WebdriverClient.visit/2
         (wallaby 0.30.9) lib/wallaby/driver/log_checker.ex:6: Wallaby.Driver.LogChecker.check_logs!/2
         (wallaby 0.30.9) lib/wallaby/browser.ex:1269: Wallaby.Browser.visit/2

The primary cause is a version mismatch between Chrome and ChromeDriver. Wallaby requires that your Chrome browser and ChromeDriver versions match at the major, minor, and build level.

To fix, just update Chrome and chromedriver. That’s it.