Dashboard Layout Regression: Widgets "shrink" horizontally after upgrading from v10 to v25 #7585
Description
Issue Summary
After upgrading our self-hosted Redash instance from v10.x to v25.1, all existing dashboards have lost their full-screen layout. Widgets that previously spanned specific widths (e.g., 50% or 33% of the screen) now appear significantly narrower, leaving large empty spaces on the right side of the dashboard.
This appears to be a migration issue where the stored integer width values for widgets (from the old grid system) were not scaled up to match the new grid system's granularity (likely the shift to a 12-column or 24-column grid).
Steps to Reproduce
Have a Redash v10.0 instance with a dashboard containing widgets set to width: 3 (spanning 50% of the screen in the old 6-column grid).
Upgrade the instance to v25.1.
Open the same dashboard.
Observation: The widgets now render much smaller (approx 25% of the screen), seemingly retaining the raw width: 3 value but applying it to a finer-grained grid (e.g., 3 columns out of 12).
Expected Behavior
The migration script should have adjusted the widget width values to preserve the relative visual proportion of the dashboard (e.g., if a widget took up 50% of the row in v10, it should take up 50% of the row in v25).
Before and after
