I often have issues with pasting into a cell. It just hangs for a minute or two, sometimes longer. I've read before that it could be because other fields need to be updated if they have have formulas that use that field. However, in my most recent case, I was simply pasting some text into a text field, and it took at least two minutes.
Sometimes Airtable is slow. Some reasons why Airtable is slow are beyond our control: - the internet is slow - Airtable's servers are especially busy - there is a lot of data to process
Sometimes the design or use of a base can affect performance: - we have a lot of formula fields that require recalculating, including inefficient formulas and rollups - there are many 3rd party API calls that we may not even be aware of - someone else in the base runs a scripts or other code making a lot of changes to the base at once, tying up resources - we have many concurrent users of the base - there are other bases in the same workspace taking up resources
I suspect that your issues of slow pasting of text into a cell is one of those intermittent things over which we have no control.