[BUG] Patch update with relayoutData no longer working after Dash 4.1 to 4.2 upgrade

[ghaarsma]

After upgrading from Dash 4.1 to Dash 4.2, a part of our Dash trending of timeseries data failed to work correctly.

Under Dash 4.1 (Python 3.14), everything works as expected in the attached MRE. You can hit forward/backward button and pan (click and drag the x-axes) the trend.

After upgrading to Dash 4.2, the forward/backward buttons still work, but when you try to pan after selecting forward/backward the panning doesn't work anymore. The figure is stuck on the prior x-axis range.

dash_patch_relayout.py

How it should look (always a diagonal line):

When first hitting forward/backward and then panning (this works fine under Dash 4.1, but not Dash 4.2):

[ghaarsma]

@camdecoster, I noticed that this bug was not (yet) triaged. I can confirm this is still a problem for us under Dash 4.4 and prevents us from upgrading. We are currently stuck on Dash 4.1

The panning bug with relayoutData can be tricky to reproduce. You first have to move backward/foward with the buttons and after that the panning in the figure via relayoutData no longer works. If you are having issues reproducing, please let me know.

[AnnMarieW]

@ghaarsma
I did try to reproduce the issue. Can you please include what Plotly version you are using with dash 4.1 and dash 4.4?

[ghaarsma]

I'm using the latest plotly version 6.8.0 for both. My only project dependency is Dash 4.1 vs Dash 4.4

Poetry Dash 4.1 to 4.4 upgrade log:

Package operations: 5 installs, 1 update, 0 removals

  - Installing annotated-types (0.7.0)
  - Installing pydantic-core (2.46.4)
  - Installing typing-inspection (0.4.2)
  - Installing janus (2.0.0)
  - Installing pydantic (2.13.4)
  - Updating dash (4.1.0 -> 4.4.0)

In order to reproduce the failures under Dash 4.4, first hit the backward/foward buttons and then pan the figure (by click and drag from the center of the x-axis). Under Dash 4.4 this pan will fail and it will snap back to it's prior x-axis limits.

@AnnMarieW , Let me know if you cannot reproduce and I can perhaps show in Zoom/Teams

[AnnMarieW]

Ok, I was able to reproduce it. Thanks for the additional info.
I expect it's from changes in this PR #3785

[ghaarsma]

@AnnMarieW, Thank you for the confirmation. I agree that PR #3785 sounds plausible, given the fact that the plotly-resampler project reports very similar issues in their own bug report.

Hope we can have this fixed in the near future.

[AnnMarieW]

@T4rk1n - Wow - that was fast! 🎉

[tlauli]

Hi, we just hit this bug too during an upgrade, glad to see it is already fixed. <3 Is a patch release planned anytime soon?

[ghaarsma]

Can confirm that is has been fixed in Dash 4.4.1. Thank you @T4rk1n for the fix and new release.