diff --git a/appengine/add_timestamps.py b/appengine/add_timestamps.py
index af877f3d6..05ff7b928 100644
--- a/appengine/add_timestamps.py
+++ b/appengine/add_timestamps.py
@@ -62,8 +62,8 @@ def run_query():
     while more:
       results, cursor, more = query.fetch_page(PAGE_SIZE, start_cursor=cursor)
       handle_results(results)
-      page_count = page_count + 1
-      result_count = result_count + len(results)
+      page_count += 1
+      result_count += len(results)
       print(f'{datetime.datetime.now().strftime("%I:%M:%S %p")} : page {page_count} : {result_count}')
 
 run_query()
diff --git a/core/field_variable.ts b/core/field_variable.ts
index 95474e4b1..539557256 100644
--- a/core/field_variable.ts
+++ b/core/field_variable.ts
@@ -444,7 +444,6 @@ export class FieldVariable extends FieldDropdown {
     // #1499.
     // Set the allowable variable types.  Null means all types on the workspace.
     if (Array.isArray(variableTypes)) {
-      variableTypes = variableTypes;
       // Make sure the default type is valid.
       let isInArray = false;
       for (let i = 0; i < variableTypes.length; i++) {
diff --git a/core/serialization/workspaces.ts b/core/serialization/workspaces.ts
index 07c909ccf..871060196 100644
--- a/core/serialization/workspaces.ts
+++ b/core/serialization/workspaces.ts
@@ -75,8 +75,7 @@ export function load(
   }
 
   // reverse() is destructive, so we have to re-reverse to correct the order.
-  for (let [name, deserializer] of deserializers.reverse()) {
-    name = name;
+  for (const [name, deserializer] of deserializers.reverse()) {
     const pluginState = state[name];
     if (pluginState) {
       (deserializer as ISerializer)?.load(state[name], workspace);
diff --git a/core/shortcut_registry.ts b/core/shortcut_registry.ts
index 35f409b48..161a2ed14 100644
--- a/core/shortcut_registry.ts
+++ b/core/shortcut_registry.ts
@@ -287,7 +287,7 @@ export class ShortcutRegistry {
       }
     }
     if (serializedKey !== '' && e.keyCode) {
-      serializedKey = serializedKey + '+' + e.keyCode;
+      serializedKey += '+' + e.keyCode;
     } else if (e.keyCode) {
       serializedKey = String(e.keyCode);
     }
@@ -335,7 +335,7 @@ export class ShortcutRegistry {
     }
 
     if (serializedKey !== '' && keyCode) {
-      serializedKey = serializedKey + '+' + keyCode;
+      serializedKey += '+' + keyCode;
     } else if (keyCode) {
       serializedKey = `${keyCode}`;
     }
diff --git a/core/utils/svg_math.ts b/core/utils/svg_math.ts
index 88d38f625..0444787ad 100644
--- a/core/utils/svg_math.ts
+++ b/core/utils/svg_math.ts
@@ -87,8 +87,8 @@ export function getInjectionDivXY(element: Element): Coordinate {
   let y = 0;
   while (element) {
     const xy = getRelativeXY(element);
-    x = x + xy.x;
-    y = y + xy.y;
+    x += xy.x;
+    y += xy.y;
     const classes = element.getAttribute('class') || '';
     if ((' ' + classes + ' ').includes(' injectionDiv ')) {
       break;
diff --git a/generators/javascript/math.ts b/generators/javascript/math.ts
index e8ab2852f..238ad19a2 100644
--- a/generators/javascript/math.ts
+++ b/generators/javascript/math.ts
@@ -318,7 +318,7 @@ function ${generator.FUNCTION_NAME_PLACEHOLDER_}(values) {
   }
   for (var j = 0; j < counts.length; j++) {
     if (counts[j][1] === maxCount) {
-        modes.push(counts[j][0]);
+      modes.push(counts[j][0]);
     }
   }
   return modes;
@@ -341,7 +341,7 @@ function ${generator.FUNCTION_NAME_PLACEHOLDER_}(numbers) {
   for (var j = 0; j < n; j++) {
     variance += Math.pow(numbers[j] - mean, 2);
   }
-  variance = variance / n;
+  variance /= n;
   return Math.sqrt(variance);
 }
 `,
diff --git a/scripts/i18n/js_to_json.py b/scripts/i18n/js_to_json.py
index c070f3408..53651935e 100755
--- a/scripts/i18n/js_to_json.py
+++ b/scripts/i18n/js_to_json.py
@@ -81,7 +81,7 @@ def main():
   for line in infile:
     if line.startswith('///'):
       if description:
-        description = description + ' ' + line[3:].strip()
+        description += ' ' + line[3:].strip()
       else:
         description = line[3:].strip()
     else:
diff --git a/tests/generators/golden/generated.js b/tests/generators/golden/generated.js
index f8ac5651a..ec103f0ba 100644
--- a/tests/generators/golden/generated.js
+++ b/tests/generators/golden/generated.js
@@ -513,7 +513,7 @@ function mathModes(values) {
   }
   for (var j = 0; j < counts.length; j++) {
     if (counts[j][1] === maxCount) {
-        modes.push(counts[j][0]);
+      modes.push(counts[j][0]);
     }
   }
   return modes;
@@ -527,7 +527,7 @@ function mathStandardDeviation(numbers) {
   for (var j = 0; j < n; j++) {
     variance += Math.pow(numbers[j] - mean, 2);
   }
-  variance = variance / n;
+  variance /= n;
   return Math.sqrt(variance);
 }
 
diff --git a/tests/generators/unittest_dart.js b/tests/generators/unittest_dart.js
index 312a8fcc2..89f355389 100644
--- a/tests/generators/unittest_dart.js
+++ b/tests/generators/unittest_dart.js
@@ -154,7 +154,7 @@ dartGenerator.forBlock['unittest_adjustindex'] = function(block) {
       return [Number(index) + 1, dartGenerator.ORDER_ATOMIC];
     } else {
       // If the index is dynamic, adjust it in code.
-      index = index + ' + 1';
+      index += ' + 1';
     }
   } else if (Blockly.utils.string.isNumber(index)) {
     return [index, dartGenerator.ORDER_ATOMIC];
diff --git a/tests/generators/unittest_javascript.js b/tests/generators/unittest_javascript.js
index 279244eb2..77953a37a 100644
--- a/tests/generators/unittest_javascript.js
+++ b/tests/generators/unittest_javascript.js
@@ -158,7 +158,7 @@ javascriptGenerator.forBlock['unittest_adjustindex'] = function(block) {
       return [Number(index) + 1, javascriptGenerator.ORDER_ATOMIC];
     } else {
       // If the index is dynamic, adjust it in code.
-      index = index + ' + 1';
+      index += ' + 1';
     }
   } else if (Blockly.utils.string.isNumber(index)) {
     return [index, javascriptGenerator.ORDER_ATOMIC];
diff --git a/tests/generators/unittest_php.js b/tests/generators/unittest_php.js
index 408960d82..aedd7e6a1 100644
--- a/tests/generators/unittest_php.js
+++ b/tests/generators/unittest_php.js
@@ -145,7 +145,7 @@ phpGenerator.forBlock['unittest_adjustindex'] = function(block) {
       return [Number(index) + 1, phpGenerator.ORDER_ATOMIC];
     } else {
       // If the index is dynamic, adjust it in code.
-      index = index + ' + 1';
+      index += ' + 1';
     }
   } else if (Blockly.utils.string.isNumber(index)) {
     return [index, phpGenerator.ORDER_ATOMIC];
diff --git a/tests/generators/unittest_python.js b/tests/generators/unittest_python.js
index ba29015f9..49f8c9100 100644
--- a/tests/generators/unittest_python.js
+++ b/tests/generators/unittest_python.js
@@ -129,7 +129,7 @@ pythonGenerator.forBlock['unittest_adjustindex'] = function(block) {
       return [Number(index) + 1, pythonGenerator.ORDER_ATOMIC];
     } else {
       // If the index is dynamic, adjust it in code.
-      index = index + ' + 1';
+      index += ' + 1';
     }
   } else if (Blockly.utils.string.isNumber(index)) {
     return [index, pythonGenerator.ORDER_ATOMIC];