diff --git a/plugins/convertPathData.js b/plugins/convertPathData.js
index 3ba5288fe..8d573ee38 100644
--- a/plugins/convertPathData.js
+++ b/plugins/convertPathData.js
@@ -394,7 +394,6 @@ function filters(
 
   path = path.filter(function (item, index, path) {
     const qControlPoint = prevQControlPoint;
-    prevQControlPoint = undefined;
 
     let command = item.command;
     let data = item.args;
@@ -895,6 +894,8 @@ function filters(
         // @ts-ignore
         prevQControlPoint = item.coords;
       }
+    } else {
+      prevQControlPoint = undefined;
     }
     prev = item;
     return true;
diff --git a/test/plugins/convertPathData.36.svg.txt b/test/plugins/convertPathData.36.svg.txt
new file mode 100644
index 000000000..69f35de57
--- /dev/null
+++ b/test/plugins/convertPathData.36.svg.txt
@@ -0,0 +1,15 @@
+Should process/optimize q correctly even if useless commands in between.
+
+See: https://github.com/svg/svgo/issues/1926
+
+===
+
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1 20">
+  <path d="M-6.3 9.9q.7-4.5.2-5-.5-.5-1.5-.5l0 0q-.4 0-2 .3"/>
+</svg>
+
+@@@
+
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1 20">
+    <path d="M-6.3 9.9q.7-4.5.2-5t-1.5-.5q-.4 0-2 .3"/>
+</svg>