diff --git a/public/js/modules/editor.js b/public/js/modules/editor.js
index 907060e..db3dace 100644
--- a/public/js/modules/editor.js
+++ b/public/js/modules/editor.js
@@ -465,11 +465,14 @@ body.addEventListener('input', () => {
 
 function getTagQuery() {
     const before = body.value.substring(0, body.selectionStart);
-    // Find # preceded by whitespace or start of line, not part of heading (# + space)
-    const m = before.match(/(?:^|[\s])#([a-zA-Z0-9_\/-]*)$/m);
-    if (!m) return null;
-    const start = before.length - m[0].length + (m[0].startsWith('#') ? 0 : 1); // skip leading whitespace
-    return { start, query: m[1] };
+    const idx = before.lastIndexOf('#');
+    if (idx < 0) return null;
+    // Must be at start or after whitespace
+    if (idx > 0 && !/\s/.test(before[idx - 1])) return null;
+    // Everything after # to cursor must be valid tag chars (or empty)
+    const query = before.substring(idx + 1);
+    if (query && /[^a-zA-Z0-9_\/-]/.test(query)) return null;
+    return { start: idx, query };
 }
 
 function getAllTags() {