yugutou Thank you for your feedback! I think this is a good point, but I think using the Sync button might be sufficient instead of adding a new feature. Have you tried using that button?:

It's not exactly a feature to zoom in on the Loop Start and End ranges, but it should be useful for aligning the zoom level displayed in the dopesheet with the range displayed in the graph.
However, I think it might be nice to have a hotkey or something to automatically align the zoom with the Loop Start and End ranges. Would you like to see such a feature? Or is the Sync button sufficient?

yugutou Sync is a feature that synchronizes the display state in the graph view with that in the dopesheet. When you change the zoom level in either the graph or the dopesheet, the zoom level in the other view will automatically adjust accordingly.
However, there is currently no feature to focus on the range delimited by Loop Start and End. If such a feature is required, it will need to be added via a new hotkey or similar method.

yugutou I thought your opinion made sense, so I created an issue ticket here to add a hotkey to solve this issue:
EsotericSoftware/spine-editor889
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