Vaadin 8.12.4 Grid AutoColumnWidthsRecalculator JavaScript Loop in connecti

Hi,

we updated Vaadin version from 8.9.4 to 8.12.4 and can now see page rendering timeouts with RESULT_CODE_HUNG or page unresponsive error popups. JavaScript showed a loop in the Grid AutoColumnWidthsRecalculator where lastCalculatedInnerWidth is jumping between two values (1126 and 1143) in connection with a VerticalScrollbarVisibilityChangeEvent. There is a verification in com.vaadin.client.widgets.Grid#onResize that prevents a loop if the value is identical, but as it is changing every two times, the verification is prevented.

It looks like this is only reproducible on Windows Chrome, not on MacOS Chrome, but there the scrollbar design is also different.

I don’t know exactly how to continue to debug or fix this and whether this could be wrong usage or if I should create a bug issue for this? I fear it will become hard to create a minimal example. Basic idea must be to have a grid that has some rows and the size should be right that a vertical scrollbar is needed or not in connection with the AutoColumnWidthsRecalculator, so it jumps between these changes forever.

Is there any detail in this change of the Vaadin version that could help in the analysis or fix of this issue?

Best regards

Jan

Created issue https://github.com/vaadin/framework/issues/12289 with all details I know so far.