Update metrics changelog for M85 and M86.

Also include a change missed in M84.

Change-Id: I0091c73b5d56fee3d326412a367a1cb85cdbd865
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2373218
Commit-Queue: Annie Sullivan <[email protected]>
Reviewed-by: Nicolás Peña Moreno <[email protected]>
Cr-Commit-Position: refs/heads/master@{#801391}
diff --git a/docs/speed/metrics_changelog/lcp.md b/docs/speed/metrics_changelog/lcp.md
index 80aabcf..5d114ddf4 100644
--- a/docs/speed/metrics_changelog/lcp.md
+++ b/docs/speed/metrics_changelog/lcp.md
@@ -2,6 +2,8 @@
 
 This is a list of changes to [Largest Contentful Paint](https://web.dev/lcp).
 
+* Chrome 86
+  * Metric definition improvement: [Largest Contentful Paint ignores paints with opacity 0](2020_08_lcp.md)
 * Chrome 83
   * Metric definition improvement: [Largest Contentful Paint measurement stops at first input or scroll](2020_05_lcp.md)
   * Metric definition improvement: [Largest Contentful Paint properly accounts for visual size of background images](2020_05_lcp.md)