Closes #22783

Summary

DayTimeGridContainer declared a --has-scroll CSS custom property that nothing reads. The real scroll state is driven by the data-has-scroll attribute, set from the React hasScroll state and consumed by the [data-has-scroll] selectors in the same file. The variable was also hardcoded to a static 1, so it would not reflect the actual state even if something did read it. This removes the dead declaration.

Change

A single line removed from the DayTimeGridContainer styled block:

})(({ theme }) => ({
  '--fixed-cell-width': `${FIXED_CELL_WIDTH}px`,
  '--hour-height': `${HOUR_HEIGHT}px`,

- '--has-scroll': 1,

  width: '100%',
  height: '100%',

Why this is safe

• A repo-wide search for var(--has-scroll) returns no consumers. The only --has-scroll reference was the declaration itself.
• The unrelated --has-scroll-x variable in the premium timeline (EventTimelinePremiumContent.tsx) is a different property and is not touched.
• The data-has-scroll attribute path (lines 79, 82, 102, 175, 179, 428, 453) is unchanged, so there is no behavior change.

Testing

No new test was added. The variable is never read so there is no observable behavior to assert, and a test checking that a CSS variable is absent would not reflect how this repo validates changes. Verification instead:

• pnpm --filter "@mui/x-scheduler" run typescript passes.
• pnpm eslint passes.
• pnpm test:unit --project "x-scheduler" --run passes (18 files, 168 tests), including the existing data-has-scroll tests in WeekView.test.tsx, which behave identically.
• Post-change grep confirms --has-scroll no longer appears anywhere in the repo.

Changelog

@mui/x-scheduler

• Remove an unused --has-scroll CSS variable from DayTimeGrid.

Checklist

• I have followed (at least) the PR section of the contributing guide.