diff --git a/browse/js/preview-yaml.js b/browse/js/preview-yaml.js
index c6b4883..fe017be 100644
--- a/browse/js/preview-yaml.js
+++ b/browse/js/preview-yaml.js
@@ -484,9 +484,14 @@
             // .zddc files without diverting into the editor. User
             // clicks (or tabs) into the editor when they want to type.
             autofocus: false,
-            // CodeMirror's "nocursor" mode is the truest read-only:
-            // selection allowed for copy, no caret, no edit affordances.
-            readOnly: !writable ? 'nocursor' : false,
+            // Read-only uses readOnly:true (NOT "nocursor"): the editor
+            // stays focusable so the user can click in, select text, and
+            // copy — they just can't edit. "nocursor" removes the textarea
+            // from focus, which also kills click-drag selection (the whole
+            // reason a viewer would otherwise force admin mode just to copy
+            // a .zddc snippet). autofocus:false keeps arrow-key tree nav
+            // intact until the user deliberately clicks into the editor.
+            readOnly: !writable,
         });
         // Stash the node on the editor so the lint helper can decide
         // whether to apply the .zddc schema layer.