# The test "our browser is outdated" can be fooled
**URL:** https://meta.discourse.org/t/the-test-our-browser-is-outdated-can-be-fooled/379951
**Category:** Bug
**Created:** [August 22, 2025, 7:01pm UTC](https://meta.discourse.org/t/the-test-our-browser-is-outdated-can-be-fooled/379951 "2025-08-22T19:01:29Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@Aneta\_Zelek](https://meta.discourse.org/u/Aneta_Zelek)
#### Post date: [August 22, 2025, 7:01pm UTC](https://meta.discourse.org/t/the-test-our-browser-is-outdated-can-be-fooled/379951/1 "2025-08-22T19:01:29Z")
I noticed that the latest check on `meta.discourse.org` or `discover.discourse.com` to avoid viewing pages in modern mode on e.g. Firefox 115.27.0 can be circumvented by uBlock Origin, AdGuard, or even AdBlock/Adblock Plus:
```plaintext
! One of the four is sufficient:
meta.discourse.org##+js(aopw, unsupportedBrowser)
! Less stable:
meta.discourse.org##+js(set, unsupportedBrowser, undefined)
meta.discourse.org##+js(set, unsupportedBrowser, false)
meta.discourse.org##+js(set, unsupportedBrowser, '')
! Once every few dozen views, race mode may occur when using the set-constant version, causing the content blocker to fail when we rely on it, and the correct preview will be enabled in simplified HTML.
```
- `aopw` = `abort-on-property-write`\[1\]
- `set` = `set-constant`\[2\]_(`override-property-read` for AdBlock and ABP)_
Perhaps it should use a more secure method? One now visible disadvantage is that footnotes inserted into replies or introductory posts definitely do not work with this trick (Perhaps it is using CSS (other than the known issue with Relative Colour Syntax) or JS that is too new).
* * *
1. [Resources Library · gorhill/uBlock Wiki · GitHub **#abort-on-property-writejs-**](https://github.com/gorhill/ublock/wiki/Resources-Library#abort-on-property-writejs-)
2. [Resources Library · gorhill/uBlock Wiki · GitHub **#set-constantjs-**](https://github.com/gorhill/ublock/wiki/Resources-Library#set-constantjs-)
---
### Author:  [@sam](https://meta.discourse.org/u/sam)
#### Post date: [August 24, 2025, 11:42pm UTC](https://meta.discourse.org/t/the-test-our-browser-is-outdated-can-be-fooled/379951/2 "2025-08-24T23:42:45Z")
Sorry, can you expand a bit.
You are saying that any default install of uBlock Origin on an old browser bypasses our check?
---
### Author:  [@Aneta\_Zelek](https://meta.discourse.org/u/Aneta_Zelek)
#### Post date: [August 25, 2025, 8:42pm UTC](https://meta.discourse.org/t/the-test-our-browser-is-outdated-can-be-fooled/379951/3 "2025-08-25T20:42:48Z")
I will add STR:
1. Install uBlock Origin from the official store in Firefox 115.27.0, as there are no major new features in the Manifest V2 API for Firefox add-ons that would cause people to stay on an outdated version of uBO (In other wide-content blockers, the steps are similar (the tab for your own filters may have a different name)).
2. Go to its settings and the “My Filters” tab.
3. Paste one of the 4 suggestions (the simplicity of all 4 filters means that there is no point in protecting the authorship, as someone came up with them at least a day before me).
4. Open or refresh the forum and the page will load in a “modern” look rather than simplified HTML (if the race condition does not occur when selecting the `set-constant`-based version).
Perhaps it is enough to enclose the “global variable” in an “anonymous function” invisible to scriptlets/spinnets of wide-spectrum content blockers, when the idea of its dynamic name, e.g. changed every 24 hours at the CDN level, is too costly for the infrastructure.
Other forums that have implemented a simple HTML system view instead of a longer transition period with a less aggressive warning bar under header navigation can be `forum.fxsound.com`, where `apow`/`set-constant` also works for now.