diff --git a/.mozilla/firefox/profile/chrome/userChrome.css b/.mozilla/firefox/profile/chrome/userChrome.css
index fad58aa..0e4155a 100644
--- a/.mozilla/firefox/profile/chrome/userChrome.css
+++ b/.mozilla/firefox/profile/chrome/userChrome.css
@@ -2,6 +2,6 @@
 @import "userChrome/topbar.css";
 
 /* 去除弹出菜单的透明边框 (与compositor冲突) */
-.menupopup-arrowscrollbox, slot:nth-child(1) {
-  margin: 0 !important;
+menupopup, panel {
+  --panel-shadow-margin: 0 !important;
 }
diff --git a/.mozilla/firefox/profile/chrome/userContent.css b/.mozilla/firefox/profile/chrome/userContent.css
new file mode 100644
index 0000000..dc9eedd
--- /dev/null
+++ b/.mozilla/firefox/profile/chrome/userContent.css
@@ -0,0 +1,7 @@
+/* Sidebery */
+@-moz-document regexp("^moz-extension://[a-zA-Z0-9-]+/sidebar/index\.html.*")
+{
+  #root .Tab .close {
+    transition: opacity 200ms ease-in;
+  }
+}