content-visibility:auto Render Skip Note

Audit explicit content-visibility and independently observed UA relevance; auto may skip rendering while retaining layout/accessibility semantics, placeholder already computed independently. Explicit supplied computed/layout context only; not a browser cascade/layout engine or cross-browser guarantee.

Description

Content visibility can allow a browser to skip eligible rendering work.

Content visibility can allow a browser to skip eligible rendering work.^[1]

A caller placeholder size preserves a geometric allowance rather than proving what the browser actually skips. Use content-visibility:auto Render Skip Note to evaluate the supplied inputs under the specific model below.

When to use content-visibility:auto Render Skip Note

Use content-visibility:auto Render Skip Note to evaluate the supplied inputs under the specific model below. Define the supplied layout, token or rendering scenario and establish the relevant units and browser context independently.

How to use content-visibility:auto Render Skip Note and understand its results

Define the supplied layout, token or rendering scenario and establish the relevant units and browser context independently.
Enter Content visibility, Ua relevant to user, Caller intrinsic placeholder height px using the field table and validation rules below, then run the tool.
Read Eligible for ua render skipping, Retained placeholder height px and interpret units, signs, ordering and placeholders as explained below.
If the tool reports an input error, correct that field and rerun. A successful false result, empty match list or unknown-evidence placeholder has the specific meaning described here; check the limitations before applying the result.

Input field	Meaning	Value type	Requirement
contentVisibility	Content visibility	string	Required; constraints below
uaRelevantToUser	Ua relevant to user	boolean	Required; constraints below
callerIntrinsicPlaceholderHeightPx	Caller intrinsic placeholder height px	number	Required; constraints below

Enter visible, auto or hidden, a nonnegative intrinsic placeholder extent and a supplied user-agent relevance boolean. Skipping eligibility is true for hidden or for auto when the content is not relevant. The retained placeholder is always returned unchanged, including visible mode. This does not inspect visibility, accessibility effects or actual rendering decisions.

eligible = hidden or (auto and !UARelevant); retainedPlaceholder = callerPlaceholder

Field order, units and branch conditions follow the implementation explanation above.

Output field	Meaning	Value type
eligibleForUaRenderSkipping	Eligible for ua render skipping	boolean
retainedPlaceholderHeightPx	Retained placeholder height px	number

json

{
  "input": {
    "contentVisibility": "auto",
    "uaRelevantToUser": false,
    "callerIntrinsicPlaceholderHeightPx": 300
  },
  "output": {
    "eligibleForUaRenderSkipping": true,
    "retainedPlaceholderHeightPx": 300
  }
}

Limitations and assumptions

A caller placeholder size preserves a geometric allowance rather than proving what the browser actually skips. Apply the exact scope and assumptions described above.

All listed fields require explicit values. Unexpected fields, incorrect types, nonfinite numbers and sparse arrays fail validation. Domain-specific bounds, alignments and supported tokens are stated above; extremely large inputs or outputs can also be rejected. These errors differ from successful results such as false, no matches or unknown evidence.

Alternative or Complementary methods

Use Reflow vs Repaint Trigger Table for a related task: Property changes can invalidate different rendering stages.

Use Layout Thrashing Read/Write Interleave Warning for a related task: A layout-dependent read after an invalidating write can require pending layout work.

References

content-visibility:auto Render Skip Note — tool.io

Similar or alternative tools

Reflow vs Repaint Trigger Table
Property changes can invalidate different rendering stages.
Layout Thrashing Read/Write Interleave Warning
A layout-dependent read after an invalidating write can require pending layout work.