diff --git a/packages/e2e-tests/fixtures/blocks/core__rss.html b/packages/e2e-tests/fixtures/blocks/core__rss.html
index ce652528301c6f..69b41ce041862b 100644
--- a/packages/e2e-tests/fixtures/blocks/core__rss.html
+++ b/packages/e2e-tests/fixtures/blocks/core__rss.html
@@ -1 +1 @@
-<!-- wp:rss {"postLayout":"grid","feedURL":"https://wordpress.org/news/","postsToShow":4,"displayExcerpt":true,"displayAuthor":true,"displayDate":true,"excerptLength":20} /-->
+<!-- wp:rss {"blockLayout":"grid","feedURL":"https://wordpress.org/news/","itemsToShow":4,"displayExcerpt":true,"displayAuthor":true,"displayDate":true,"excerptLength":20} /-->
diff --git a/packages/e2e-tests/fixtures/blocks/core__rss.json b/packages/e2e-tests/fixtures/blocks/core__rss.json
index 89de06cd2d78d5..09f43cf2e1e253 100644
--- a/packages/e2e-tests/fixtures/blocks/core__rss.json
+++ b/packages/e2e-tests/fixtures/blocks/core__rss.json
@@ -3,7 +3,16 @@
         "clientId": "_clientId_0",
         "name": "core/rss",
         "isValid": true,
-        "attributes": {},
+        "attributes": {
+            "columns": 2,
+            "blockLayout": "grid",
+            "feedURL": "https://wordpress.org/news/",
+            "itemsToShow": 4,
+            "displayExcerpt": true,
+            "displayAuthor": true,
+            "displayDate": true,
+            "excerptLength": 20
+        },
         "innerBlocks": [],
         "originalContent": ""
     }
diff --git a/packages/e2e-tests/fixtures/blocks/core__rss.parsed.json b/packages/e2e-tests/fixtures/blocks/core__rss.parsed.json
index bdc596b09a5a1b..e55306214e219c 100644
--- a/packages/e2e-tests/fixtures/blocks/core__rss.parsed.json
+++ b/packages/e2e-tests/fixtures/blocks/core__rss.parsed.json
@@ -2,9 +2,9 @@
     {
         "blockName": "core/rss",
         "attrs": {
-            "postLayout": "grid",
+            "blockLayout": "grid",
             "feedURL": "https://wordpress.org/news/",
-            "postsToShow": 4,
+            "itemsToShow": 4,
             "displayExcerpt": true,
             "displayAuthor": true,
             "displayDate": true,
diff --git a/packages/e2e-tests/fixtures/blocks/core__rss.serialized.html b/packages/e2e-tests/fixtures/blocks/core__rss.serialized.html
index c6d9be22646e74..69b41ce041862b 100644
--- a/packages/e2e-tests/fixtures/blocks/core__rss.serialized.html
+++ b/packages/e2e-tests/fixtures/blocks/core__rss.serialized.html
@@ -1 +1 @@
-<!-- wp:rss /-->
+<!-- wp:rss {"blockLayout":"grid","feedURL":"https://wordpress.org/news/","itemsToShow":4,"displayExcerpt":true,"displayAuthor":true,"displayDate":true,"excerptLength":20} /-->
diff --git a/packages/e2e-tests/fixtures/blocks/core__search.json b/packages/e2e-tests/fixtures/blocks/core__search.json
index e1397fdc9a37aa..dbf8ea090062ed 100644
--- a/packages/e2e-tests/fixtures/blocks/core__search.json
+++ b/packages/e2e-tests/fixtures/blocks/core__search.json
@@ -3,7 +3,11 @@
         "clientId": "_clientId_0",
         "name": "core/search",
         "isValid": true,
-        "attributes": {},
+        "attributes": {
+            "label": "Search",
+            "placeholder": "",
+            "buttonText": "Search"
+        },
         "innerBlocks": [],
         "originalContent": ""
     }
diff --git a/packages/e2e-tests/fixtures/blocks/core__search__custom-text.json b/packages/e2e-tests/fixtures/blocks/core__search__custom-text.json
index e1397fdc9a37aa..fb91161919c83e 100644
--- a/packages/e2e-tests/fixtures/blocks/core__search__custom-text.json
+++ b/packages/e2e-tests/fixtures/blocks/core__search__custom-text.json
@@ -3,7 +3,11 @@
         "clientId": "_clientId_0",
         "name": "core/search",
         "isValid": true,
-        "attributes": {},
+        "attributes": {
+            "label": "Custom label",
+            "placeholder": "Custom placeholder",
+            "buttonText": "Custom button text"
+        },
         "innerBlocks": [],
         "originalContent": ""
     }
diff --git a/packages/e2e-tests/fixtures/blocks/core__search__custom-text.parsed.json b/packages/e2e-tests/fixtures/blocks/core__search__custom-text.parsed.json
index fd128b35f93c81..6b67b6d21a472e 100644
--- a/packages/e2e-tests/fixtures/blocks/core__search__custom-text.parsed.json
+++ b/packages/e2e-tests/fixtures/blocks/core__search__custom-text.parsed.json
@@ -2,9 +2,9 @@
     {
         "blockName": "core/search",
         "attrs": {
-            "buttonText": "Custom button text",
             "label": "Custom label",
-            "placeholder": "Custom placeholder"
+            "placeholder": "Custom placeholder",
+            "buttonText": "Custom button text"
         },
         "innerBlocks": [],
         "innerHTML": "",
diff --git a/packages/e2e-tests/fixtures/blocks/core__search__custom-text.serialized.html b/packages/e2e-tests/fixtures/blocks/core__search__custom-text.serialized.html
index f62e8a853c2eaa..bb6e6a56c9a339 100644
--- a/packages/e2e-tests/fixtures/blocks/core__search__custom-text.serialized.html
+++ b/packages/e2e-tests/fixtures/blocks/core__search__custom-text.serialized.html
@@ -1 +1 @@
-<!-- wp:search /-->
+<!-- wp:search {"label":"Custom label","placeholder":"Custom placeholder","buttonText":"Custom button text"} /-->
diff --git a/test/integration/full-content/server-registered.json b/test/integration/full-content/server-registered.json
index 080865f39bb108..eeae11cb99e9ce 100644
--- a/test/integration/full-content/server-registered.json
+++ b/test/integration/full-content/server-registered.json
@@ -1 +1 @@
-{"core\/block":{"attributes":{"ref":{"type":"number"}}},"core\/latest-comments":{"attributes":{"className":{"type":"string"},"commentsToShow":{"type":"number","default":5,"minimum":1,"maximum":100},"displayAvatar":{"type":"boolean","default":true},"displayDate":{"type":"boolean","default":true},"displayExcerpt":{"type":"boolean","default":true},"align":{"type":"string","enum":["center","left","right","wide","full",""]}}},"core\/archives":{"attributes":{"align":{"type":"string"},"className":{"type":"string"},"displayAsDropdown":{"type":"boolean","default":false},"showPostCounts":{"type":"boolean","default":false}}},"core\/latest-posts":{"attributes":{"categories":{"type":"string"},"className":{"type":"string"},"postsToShow":{"type":"number","default":5},"displayPostDate":{"type":"boolean","default":false},"postLayout":{"type":"string","default":"list"},"columns":{"type":"number","default":3},"align":{"type":"string"},"order":{"type":"string","default":"desc"},"orderBy":{"type":"string","default":"date"}}},"core\/tag-cloud":{"attributes":{"taxonomy":{"type":"string","default":"tags"},"className":{"type":"string"},"showTagCounts":{"type":"boolean","default":false},"align":{"type":"string"}}}}
\ No newline at end of file
+{"core\/block":{"attributes":{"ref":{"type":"number"}}},"core\/latest-comments":{"attributes":{"className":{"type":"string"},"commentsToShow":{"type":"number","default":5,"minimum":1,"maximum":100},"displayAvatar":{"type":"boolean","default":true},"displayDate":{"type":"boolean","default":true},"displayExcerpt":{"type":"boolean","default":true},"align":{"type":"string","enum":["center","left","right","wide","full",""]}}},"core\/archives":{"attributes":{"align":{"type":"string"},"className":{"type":"string"},"displayAsDropdown":{"type":"boolean","default":false},"showPostCounts":{"type":"boolean","default":false}}},"core\/calendar":{"attributes":{"align":{"type":"string"},"className":{"type":"string"},"month":{"type":"integer"},"year":{"type":"integer"}}},"core\/latest-posts":{"attributes":{"categories":{"type":"string"},"className":{"type":"string"},"postsToShow":{"type":"number","default":5},"displayPostDate":{"type":"boolean","default":false},"postLayout":{"type":"string","default":"list"},"columns":{"type":"number","default":3},"align":{"type":"string"},"order":{"type":"string","default":"desc"},"orderBy":{"type":"string","default":"date"}}},"core\/rss":{"attributes":{"columns":{"type":"number","default":2},"blockLayout":{"type":"string","default":"list"},"feedURL":{"type":"string","default":""},"itemsToShow":{"type":"number","default":5},"displayExcerpt":{"type":"boolean","default":false},"displayAuthor":{"type":"boolean","default":false},"displayDate":{"type":"boolean","default":false},"excerptLength":{"type":"number","default":55}}},"core\/search":{"attributes":{"label":{"type":"string","default":"Search"},"placeholder":{"type":"string","default":""},"buttonText":{"type":"string","default":"Search"}}},"core\/tag-cloud":{"attributes":{"taxonomy":{"type":"string","default":"post_tag"},"className":{"type":"string"},"showTagCounts":{"type":"boolean","default":false},"align":{"type":"string"}}}}
\ No newline at end of file