In 7 days graphs show inbox mails as "red"

[micz]

It could be displayed like this:

Color coded bars that show "filed away" mails as blue and "residual mails" as red.
The idea would then to "eliminate the red portion", which is basically emails that are hanging around in the inbox folders.

The feature has to be activable using an option.

[props Axel Grude]

[micz]

Use stacked bar chart: https://www.chartjs.org/docs/latest/samples/bar/stacked.html