will-change Hints Properties List
Supported will-change hints with possible resource/stacking effects, not guaranteed compositing or performance improvement. Explicit supplied computed/layout context only; not a browser cascade/layout engine or cross-browser guarantee.
Description
Will-change tells a browser about an anticipated change.
Will-change tells a browser about an anticipated change.1
A hint can affect rendering contexts without guaranteeing a performance improvement or compositor promotion. Use will-change Hints Properties List to look up a supported term.
When to use will-change Hints Properties List
Use will-change Hints Properties List to look up a supported term. Choose the exact supported token from the table; preserve its punctuation and capitalization.
How to use will-change Hints Properties List and understand its results
- Choose the exact supported token from the table; preserve its punctuation and capitalization.
- Enter Hinted property using the field table and validation rules below, then run the tool.
- Read Meaning 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 |
|---|---|---|---|
| hintedProperty | Hinted property | string | Required; constraints below |
Enter one of the exact supported hintedProperty tokens in the table below. The implementation performs a case-sensitive lookup and returns the stored meaning without interpreting a stylesheet, audio recording or performance. Unsupported tokens, added whitespace and alternate capitalization are input errors. The entries describe a bounded vocabulary rather than every valid value in the wider topic.
meaning = storedTable[exactSupportedToken] Field order, units and branch conditions follow the implementation explanation above.
| Exact supported token | Stored meaning |
|---|---|
| transform | hint of upcoming transform change, may create applicable stacking/containing context early |
| opacity | hint of upcoming opacity change, may create stacking context early |
| scroll-position | hint of upcoming scroll-position change |
| contents | hint that contents may change |
| Output field | Meaning | Value type |
|---|---|---|
| meaning | Stored explanation for the exact supported token. | string |
{
"input": {
"hintedProperty": "transform"
},
"output": {
"meaning": "hint of upcoming transform change, may create applicable stacking/containing context early"
}
}Limitations and assumptions
A hint can affect rendering contexts without guaranteeing a performance improvement or compositor promotion. 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 z-index Stacking Context Boundary Check for a related task: A stacking context groups local paint-order comparisons within a larger hierarchy.
Use isolation Stacking Context Fix Note for a related task: Isolation can create a stacking context and restrict blending with the outside backdrop.
References
-
will-change Hints Properties List — tool.io
Similar or alternative tools
- z-index Stacking Context Boundary Check
A stacking context groups local paint-order comparisons within a larger hierarchy.
- isolation Stacking Context Fix Note
Isolation can create a stacking context and restrict blending with the outside backdrop.