Carlos Fenollosa — Blog

Thoughts on science and tips for researchers who use computers

Disable asmjs on Firefox on OpenBSD to render some pages like Protonmail

October 11, 2018 — Carlos Fenollosa

I've been using OpenBSD for a few weeks and Firefox is of course my browser of choice. However, I found that some pages didn't load properly, like Protonmail.

I tried increasing the memory per-process in login.conf but it didn't solve the issue.

After some googling I found an obscure reference on a Linux forum about asm.js was causing trouble. And indeed, that is the case for OpenBSD.

The solution is easy: type about:config on the URL bar, accept the disclaimer, and set the preference javascript.options.asmjs to false.

I still don't know why this happens, and if it will affect performance on other websites, so I have it enabled by default and only disable it temporarily for specific websites.

In summary, if you have problems loading websites with Firefox on OpenBSD, try disabling asm.js.

Tags: openbsd

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