diff --git a/app/javascript/styles/mastodon-bird-ui/layout-multiple-columns.scss b/app/javascript/styles/mastodon-bird-ui/layout-multiple-columns.scss
index ad7f868ac04c23..6317370dbb30e7 100644
--- a/app/javascript/styles/mastodon-bird-ui/layout-multiple-columns.scss
+++ b/app/javascript/styles/mastodon-bird-ui/layout-multiple-columns.scss
@@ -1,5 +1,5 @@
 /* Mastodon Bird UI by @rolle@mementomori.social
-   2.0.0rc36 */
+   2.0.0rc37 */
 
 /* CSS variables */
 :root {
@@ -444,6 +444,11 @@ body.layout-multiple-columns {
   width: 50px;
 }
 
+/* Fixes a regression for 4.3.0-alpha.3-2024-04-06 caused by https://github.com/mastodon/mastodon/commit/4f068d4fcc4d134fcbd56faa8f39c608dd343417 */
+.layout-multiple-columns .ui__header__logo {
+  flex-grow: unset;
+}
+
 .layout-multiple-columns .ui__header__logo img,
 .layout-multiple-columns .ui__header__logo svg {
   display: none;
diff --git a/app/javascript/styles/mastodon-bird-ui/layout-single-column.scss b/app/javascript/styles/mastodon-bird-ui/layout-single-column.scss
index f55d06f3f919ff..1f7011e3bb9ec9 100644
--- a/app/javascript/styles/mastodon-bird-ui/layout-single-column.scss
+++ b/app/javascript/styles/mastodon-bird-ui/layout-single-column.scss
@@ -1,5 +1,5 @@
 /* Mastodon Bird UI by @rolle@mementomori.social
-   2.0.0rc36 */
+   2.0.0rc37 */
 
 /* CSS variables */
 :root {
@@ -458,6 +458,11 @@ body.layout-single-column {
   display: none;
 }
 
+/* Fixes a regression for 4.3.0-alpha.3-2024-04-06 caused by https://github.com/mastodon/mastodon/commit/4f068d4fcc4d134fcbd56faa8f39c608dd343417 */
+.layout-single-column .ui__header__logo {
+  flex-grow: unset;
+}
+
 /* Things that should have the default font-size */
 .layout-single-column .notification__message,
 .layout-single-column .status__content,