I'm using this flow:
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To display image snapshots on the dashboard. Forget about the inefficiency of reading a temp file and then deleting it instead of sending an image buffer as the MQTT message, this quickly let me get something going to test.
I opened the dashboard again after several days of no use and its still showing the last images that were displayed -- despite them being gone from the disk. I cleared my browser cache and reloaded the page, the old images are still there!
I'd really rather have no image instead of something old and stale showing up!
