Just installed your plugin on Indigo 7.4, using MacOS Mojave.
The configuration failed to register, log entries indicated:
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Traceback (most recent call last):
File "plugin.py", line 155, in validatePrefsConfigUi
KeyError: key updateFrequency not found in dict
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Other errors within the log file show:
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Traceback (most recent call last):
File "plugin.py", line 74, in runConcurrentThread
AttributeError: 'Plugin' object has no attribute 'twilioClient'
Twilio Error plugin runConcurrentThread function returned or failed (will attempt again in 10 seconds)
Twilio Error Error in plugin execution runConcurrentThread:
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I'm kinda guessing here that Mojave isn't supported.