diff --git a/tool/tagger.html b/tool/tagger.html
index 453bf7e..62bde74 100644
--- a/tool/tagger.html
+++ b/tool/tagger.html
@@ -189,8 +189,14 @@ function isVideo(name) {
 // Which items this session presents. The server never filters: /media/{index}
 // and /api/tag both index the full list, so a shorter list here would show
 // item i of the album while tagging item i of the filtered set.
+// Anything seen this session stays navigable even once it has tags. Without
+// this, tagging an item removes it from the set and the left arrow jumps
+// straight over your own work -- so a mis-tag is unreachable and the only way
+// back is to restart without --untagged.
+const visited = new Set();
+
 function shown(index) {
-  return !state.untagged_only || !state.files[index].keys.length;
+  return !state.untagged_only || !state.files[index].keys.length || visited.has(index);
 }
 
 function step(from, direction) {
@@ -201,6 +207,7 @@ function step(from, direction) {
 }
 
 function draw() {
+  visited.add(at);
   const item = state.files[at];
   document.getElementById("progress").textContent =
     `${at + 1} / ${state.files.length} — ${item.name}`;