Excel for Windows has supported adding Shapes inside (not over) Charts for many years.
Excel Online does not (if a Chart contains Shapes, they will not be displayed)
Would it be possible to support this feature in Excel Online?
For instance, in my company, we rely heavily on arrows to show CAGRs.
The Shapes being inside the Chart makes it easy to move of Copy / Paste a chart with the arrows.
This is only an example of what Shapes inside charts can be bring.
Here's what it looks like in Windows:
And here's what it looks like in the browser: