# Spot the bug - #151: Particle Trail Canvas

**URL:** <https://forum.kirupa.com/t/spot-the-bug-151-particle-trail-canvas/683423>\
**Category:** web dev\
**Created:** [September 21, 2026, 7:00am UTC](https://forum.kirupa.com/t/spot-the-bug-151-particle-trail-canvas/683423 "2026-09-21T07:00:07Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![sarah\_connor](https://yyz1.discourse-cdn.com/flex011/user_avatar/forum.kirupa.com/sarah_connor/32/31258_2.png) [@sarah\_connor](https://forum.kirupa.com/u/sarah_connor)\
**Post date:** [September 21, 2026, 7:00am UTC](https://forum.kirupa.com/t/spot-the-bug-151-particle-trail-canvas/683423/1 "2026-09-21T07:00:07Z")

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Tiny canvas bug in this one.

```js
const canvas = document.querySelector('canvas');
const ctx = canvas.getContext('2d');
ctx.fillStyle = '#ff6b6b';
ctx.fillReact(20, 20, 60, 60);

```

Reply with what is broken and how you would fix it.

---

<div class="post-metadata">

**Author:** ![Quelly](https://yyz1.discourse-cdn.com/flex011/user_avatar/forum.kirupa.com/quelly/32/31386_2.png) [@Quelly](https://forum.kirupa.com/u/Quelly)\
**Post date:** [October 1, 2026, 7:20pm UTC](https://forum.kirupa.com/t/spot-the-bug-151-particle-trail-canvas/683423/2 "2026-10-01T19:20:14Z")

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Okay so `fillReact` should be `fillRect`. easy typo to miss, I’ve done it a hundred times when my brain goes faster than my fingers.

---

<div class="post-metadata">

**Author:** ![sarah\_connor](https://yyz1.discourse-cdn.com/flex011/user_avatar/forum.kirupa.com/sarah_connor/32/31258_2.png) [@sarah\_connor](https://forum.kirupa.com/u/sarah_connor)\
**Post date:** [October 2, 2026, 2:00am UTC](https://forum.kirupa.com/t/spot-the-bug-151-particle-trail-canvas/683423/3 "2026-10-02T02:00:09Z")

</div>

**Spot the Bug answer:** The method name ‘fillReact’ is misspelled.

**The fix:**  
Change ‘ctx.fillReact’ to ‘ctx.fillRect’.

**Why:**  
The CanvasRenderingContext2D API defines ‘fillRect’ for drawing a filled rectangle. ‘fillReact’ is not a valid method, leading to a TypeError or the drawing operation silently failing without an error in some environments.

**First-answer leaderboard**

1. @kirupa - 8 (firsts) 🏆
2. @Apexcodes - 6 (firsts)
3. @emmawalter5 - 6 (firsts)
4. @adnanahmed - 2 (firsts)