Hey @david
Well it disappeared overnight, for the 4th time, but when I go to my Gsheet it is still there.
and reappearing after a refresh in GDE.
I can’t record when its disappearing because it’s happening randomly, but we’ve been discussing with @Mark yesterday, and the tab definitely existed then along with the relations.
so that means it has indeed disappeared
Hope that clarifies
Ok guys!
Found the culprit, the ImportRange formula randomly throws Internal Error hence killing the page, then fixes itself and puts the page back up 
I read Using ImportRange to Export Emails in App:Logins to Another Google Sheet and saw the accepted solution, will try and hopefully this one does not break
thanks for your answers and keep the excellent work
Interesting – so sometimes the table goes empty temporarily?
ouch!
Here’s a tip: If you’re going to use IMPORTRANGE, keep your column headers fixed and start the IMPORTRANGE at the second row. At least then if/when it breaks it won’t blow away any Glide components that use that sheet.
The downside is that it risks breaking if columns change in the source sheet, but I think that’s the lesser of two evils.
Correct
definitely worth it
Thanks for the tip!!
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