From 8571c4ce2c598da484f13feed752e7f92c466e18 Mon Sep 17 00:00:00 2001 From: Barry Pollard Date: Tue, 14 Oct 2025 21:56:18 +0100 Subject: [PATCH 1/6] FID to INP --- features/event-timing.yml | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/features/event-timing.yml b/features/event-timing.yml index 285c47c6f67..a0e11299e0a 100644 --- a/features/event-timing.yml +++ b/features/event-timing.yml @@ -1,5 +1,5 @@ name: Event timing -description: The `event` and `first-input` performance entries and the `PerformanceEventTiming` API measures the latency of user input events, such as mouse clicks or keypresses, and the latency of the first user input. First Input Delay (FID) is a common metric for perceived responsiveness. +description: The `event` and `first-input` performance entries and the `PerformanceEventTiming` API measures the latency of user input events, such as mouse clicks or keypresses until the next rendering paint. Interaction to Next Paint (INP) is a common metric for perceived responsiveness. spec: https://w3c.github.io/event-timing/ group: performance status: From 4788cd897f2e0b3fbaea5a69ca989adf8f748e8b Mon Sep 17 00:00:00 2001 From: Barry Pollard Date: Tue, 14 Oct 2025 21:59:29 +0100 Subject: [PATCH 2/6] Add CLS description too --- features/layout-instability.yml | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/features/layout-instability.yml b/features/layout-instability.yml index c68a131793e..64c55746d8a 100644 --- a/features/layout-instability.yml +++ b/features/layout-instability.yml @@ -1,5 +1,5 @@ name: Layout instability -description: The `layout-shift` performance entry and `LayoutShift` API measures the layout stability of web pages based on movements of the elements on the page. +description: The `layout-shift` performance entry and `LayoutShift` API measures the layout stability of web pages based on movements of the elements on the page. Cumulative Layout Shift (CLS) is a common metric for perceived stability. spec: https://wicg.github.io/layout-instability/ group: performance compat_features: From 31933a91115544f69e726a97c357b3a35615ac3b Mon Sep 17 00:00:00 2001 From: Barry Pollard Date: Tue, 14 Oct 2025 22:01:17 +0100 Subject: [PATCH 3/6] Explain why metric is related to API --- features/event-timing.yml | 2 +- features/layout-instability.yml | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/features/event-timing.yml b/features/event-timing.yml index a0e11299e0a..bb5f8aa0a36 100644 --- a/features/event-timing.yml +++ b/features/event-timing.yml @@ -1,5 +1,5 @@ name: Event timing -description: The `event` and `first-input` performance entries and the `PerformanceEventTiming` API measures the latency of user input events, such as mouse clicks or keypresses until the next rendering paint. Interaction to Next Paint (INP) is a common metric for perceived responsiveness. +description: The `event` and `first-input` performance entries and the `PerformanceEventTiming` API measures the latency of user input events, such as mouse clicks or keypresses until the next rendering paint. Interaction to Next Paint (INP) is a common metric for perceived responsiveness calculated from the Event Timing API. spec: https://w3c.github.io/event-timing/ group: performance status: diff --git a/features/layout-instability.yml b/features/layout-instability.yml index 64c55746d8a..7a9f9f0a085 100644 --- a/features/layout-instability.yml +++ b/features/layout-instability.yml @@ -1,5 +1,5 @@ name: Layout instability -description: The `layout-shift` performance entry and `LayoutShift` API measures the layout stability of web pages based on movements of the elements on the page. Cumulative Layout Shift (CLS) is a common metric for perceived stability. +description: The `layout-shift` performance entry and `LayoutShift` API measures the layout stability of web pages based on movements of the elements on the page. Cumulative Layout Shift (CLS) is a common metric for perceived stability calculated from the Layout Instability API. spec: https://wicg.github.io/layout-instability/ group: performance compat_features: From b7f008559bb9faefde30fa755e02234c18e6b9ae Mon Sep 17 00:00:00 2001 From: Barry Pollard Date: Tue, 14 Oct 2025 22:07:41 +0100 Subject: [PATCH 4/6] Shorten description --- features/event-timing.yml | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/features/event-timing.yml b/features/event-timing.yml index bb5f8aa0a36..66a38bb84ba 100644 --- a/features/event-timing.yml +++ b/features/event-timing.yml @@ -1,5 +1,5 @@ name: Event timing -description: The `event` and `first-input` performance entries and the `PerformanceEventTiming` API measures the latency of user input events, such as mouse clicks or keypresses until the next rendering paint. Interaction to Next Paint (INP) is a common metric for perceived responsiveness calculated from the Event Timing API. +description: The `event` and `first-input` performance entries of the `PerformanceEventTiming` interface measures the latency of user input events, such as mouse clicks or keypresses. Interaction to Next Paint (INP) is a common metric for perceived responsiveness calculated from the Event Timing API. spec: https://w3c.github.io/event-timing/ group: performance status: From 813fdb6c93e9dcca46986df32aef6b7135db8521 Mon Sep 17 00:00:00 2001 From: Barry Pollard Date: Mon, 20 Oct 2025 09:56:50 +0100 Subject: [PATCH 5/6] Update features/event-timing.yml Co-authored-by: Daniel D. Beck --- features/event-timing.yml | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/features/event-timing.yml b/features/event-timing.yml index 66a38bb84ba..1dd93d918c4 100644 --- a/features/event-timing.yml +++ b/features/event-timing.yml @@ -1,5 +1,5 @@ name: Event timing -description: The `event` and `first-input` performance entries of the `PerformanceEventTiming` interface measures the latency of user input events, such as mouse clicks or keypresses. Interaction to Next Paint (INP) is a common metric for perceived responsiveness calculated from the Event Timing API. +description: The `event` and `first-input` performance entries and the `PerformanceEventTiming` API measures the latency of user input events, such as mouse clicks or keypresses. They're used to calculate Interaction to Next Paint (INP), a common metric for perceived responsiveness. spec: https://w3c.github.io/event-timing/ group: performance status: From de9f43d2e1a520ad503f43445afe22d8b0311e56 Mon Sep 17 00:00:00 2001 From: Barry Pollard Date: Mon, 20 Oct 2025 09:57:25 +0100 Subject: [PATCH 6/6] Update features/layout-instability.yml Co-authored-by: Daniel D. Beck --- features/layout-instability.yml | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/features/layout-instability.yml b/features/layout-instability.yml index 7a9f9f0a085..78c645c13a5 100644 --- a/features/layout-instability.yml +++ b/features/layout-instability.yml @@ -1,5 +1,5 @@ name: Layout instability -description: The `layout-shift` performance entry and `LayoutShift` API measures the layout stability of web pages based on movements of the elements on the page. Cumulative Layout Shift (CLS) is a common metric for perceived stability calculated from the Layout Instability API. +description: The `layout-shift` performance entry and `LayoutShift` API measures the layout stability of web pages based on movements of the elements on the page. They're used to calculate Cumulative Layout Shift (CLS), a common metric for perceived stability. spec: https://wicg.github.io/layout-instability/ group: performance compat_features: