Drop the -webkit prefix from user-select CSS rule in ui/.

ui/webui/resources/css/tree.css

Index: ui/webui/resources/css/tree.css
diff --git a/ui/webui/resources/css/tree.css b/ui/webui/resources/css/tree.css
index 2681f5e70f99f65564cf422d361a4679c7a1b0cb..8b1e368e1dd74ba4e7e8feac0df52c6a2e3d0b49 100644
--- a/ui/webui/resources/css/tree.css
+++ b/ui/webui/resources/css/tree.css
@@ -9,7 +9,6 @@ tree {
 }
 
 .tree-item > .tree-row {
-  -webkit-user-select: none;
   background-color: rgba(255, 255, 255, 0);
   border: 1px solid rgba(255, 255, 255, 0); /* transparent white */
   border-radius: 2px;
@@ -18,6 +17,7 @@ tree {
   line-height: 28px;
   padding: 0 3px;
   position: relative;
+  user-select: none;
   white-space: nowrap;
 }
 
@@ -152,10 +152,10 @@ tree[icon-visibility=parent] .tree-row[has-children=false] > .tree-label {
 
 .tree-rename > .tree-row > .tree-label {
   -webkit-user-modify: read-write-plaintext-only;
-  -webkit-user-select: auto;
   background: white;
   color: black;
   outline: 1px solid black;
+  user-select: auto;
 }
 
 .tree-item[editing] input {