Add sync feature for pan/zoom to graph card

[Aaroneisele55]

Hello,

I love the new feature of zooming and panning in graph cards as well as in the history panel.
However, when I want to check the graph of multiple entities, with different units but on the same graph card (e.g hot water heater flowrate (l/h) and hot water temperature (°C)), I often find it hard to align the two coordinate systems so that the same time range is shown for both of them.

Thus, I would like to propose the addition of a feature that, when enabled for a graph card, synchronizes the zooming and panning so the same timeframe is shown in all of the coordinate systems on that card.

In the attached screenshot I deliberately only zoomed on one of the graphs to show how they are out of sync:

This would be incredibly useful for diagnosing both automation issues (e.g “lighting didn’t turn on - was it too bright or was the sun angle condition in my automation wrong?”) as well as other technical issues (e.g “water for a bath not getting warm enough”, I would pull up a graph of the flow rate, the pellet heater duty cycle and the temperature, zoom in on the timeframe with the high flowrate, and the timeframe for the temperature and duty cycle would be adjusted automatically to show the same period of time so I can see whether the heater did heat up the hot water tank or it was low on fuel, or whether something else didn't work).

Best regards
Aaron

[wrfz]

I also sorely miss this feature.
Regularly, I need to monitor and analyze multiple sensors from my air heat pump (supply temperature, return temperature, flow rate, etc.) in combination.
When zooming in on individual graphs and adjusting the time frame, the graphs become misaligned. A small button (e.g., a lock or something similar) placed somewhere at the top would be very handy to keep the graphs synchronized.

[bartkummel]

As an addition to this:

• It would be very helpful to show the vertical line/ruler that appears under the cursor when you hover a graph on all graphs in the same card. So when you hover 1 graph, the ruler would appear on the same time-axis position in all graphs. That would make it even more easy to diagnose issues that occurred at a specific time.
• Everything described in this issue would also be helpful to have in the main history view of HA.