# Rendering 'TypeError' with theme components after update

**URL:** https://meta.discourse.org/t/rendering-typeerror-with-theme-components-after-update/381263
**Category:** Bug
**Created:** [September 2, 2025, 10:10am UTC](https://meta.discourse.org/t/rendering-typeerror-with-theme-components-after-update/381263 "2025-09-02T10:10:38Z")
**Posts on this page:** 1
**Showing post:** 1

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### Author: ![piffy](https://sea3.discourse-cdn.com/meta/user_avatar/meta.discourse.org/piffy/32/254198_2.png) [@piffy](https://meta.discourse.org/u/piffy)
#### Post date: [September 2, 2025, 10:10am UTC](https://meta.discourse.org/t/rendering-typeerror-with-theme-components-after-update/381263/1 "2025-09-02T10:10:38Z")

</div>

I just updated to this : [Commits · discourse/discourse · GitHub](https://github.com/discourse/discourse/commits/2f398db9b66f19220b5a7f56721a68f41dcdeeec) 2f398db9b66f19220b5a7f56721a68f41dcdeeec

Two different theme components now completely break my site. They are the “Modern Category + Group Boxes” from [Air Theme](https://meta.discourse.org/t/air-theme/197703) and [Avatar Size and Shape](https://meta.discourse.org/t/avatar-size-and-shape/106124)

They render the site unusable (looping?). Happens on both Firefox and Chrome (desktop)

 ![image](https://global.discourse-cdn.com/meta/original/4X/8/a/3/8a3bea2bd3549c1632eab8510dec320e99aa3714.png)

I have tried them with no plugins and in isolation on different themes (ie [safe mode](https://meta.discourse.org/t/53504?silent=true) with no plugins and on an isolated theme), so I don’t think it’s specific to my instance.

Console reports lines like this:

> Uncaught TypeError: Cannot read properties of null (reading ‘syscall’)

> Uncaught (in promise) TypeError: Invalid value used as weak map key

> message-bus.js:118 MESSAGE BUS FAIL: callback /latest caused exception TypeError: Cannot read properties of null (reading ‘syscall’)

As a temporary solution, I have forced my users onto a generic theme until it’s figured out. Please let me know if you can replicate this error.

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_[View the full topic](https://meta.discourse.org/t/rendering-typeerror-with-theme-components-after-update/381263)._