Is your feature request related to a problem? Please describe.
If there is no data for a whole account at all, the whole chart section doesn't show up correctly with an icon/notice, that there is no data. But if there is no data for a specific chart, the chart area is currently just empty, without any further notice.

Describe the solution you'd like
An icon/notice if no data is available instead of the empty chart. Possibly empty charts are:

• Most received from
• Most sent to
• Flagged as Junk
• Tags

Describe alternatives you've considered
An icon is not necessary

Additional context
None