Autocomplete's listbox Paper defaults to elevation 1, while Select/Menu's Popover defaults to elevation 8 — inconsistent shadow between components with the same UI role

[trabati]

Steps to reproduce

1. Open this link to live example: https://stackblitz.com/edit/gn7fmuvs?file=src%2FDemo.tsx
2. Compare the box-shadow of the open Select's Menu Paper vs. the open Autocomplete's listbox Paper

Current behavior

The Select's Menu Paper defaults to `elevation={8}

The Autocomplete's listbox Paper renders with no explicit elevation passed in paperProps, so it falls back to Paper's own default of elevation={1}:

Two components that serve the same UI purpose — a floating list of selectable options anchored to a field — render with visibly different shadow depth by default.

Expected behavior

Either:

• Autocomplete's listbox Paper should default to the same elevation as Select/Menu's Popover (8), since both are "floating option list" surfaces anchored to a field
  and are commonly used interchangeably in the same UI (e.g. a filter bar mixing plain Selects and Autocompletes), or
• If the difference is intentional (e.g. Autocomplete is meant to read as a lighter-weight surface), this should be documented, so it's clear the mismatch has to be
  fixed manually via slotProps={{ paper: { elevation: 8 } }} when visual parity with Select is wanted.

Context

No response

Your environment

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[silviuaavram]

So there's a workaround. We should decide if we want to go for consistency and do the change.

[silviuaavram]

This is a breaking change. Might consider it for the next major.

[namansancheti]

@silviuaavram
I would like to work on this - can you please clarify the Expected behavior ?
Will then go ahead and raise PR.