gatsby-plugin-preact with Gatsby 3 incorrectly renders "<meta http-equiv>"

Description

Gatsby 2 (with and without preact), and Gatsby 3 (without preact) all correctly generate:

<meta http-equiv="x-ua-compatible" content="ie=edge">

in the head, but Gatsby 3 with Preact (and preact plugin 5.0) instead generate:

<meta httpequiv="x-ua-compatible" content="ie=edge">

note httpequiv instead of http-equiv.

Steps to reproduce

Minimal repro:

1. npm init gatsby with basic settings
2. npm install gatsby-plugin-preact preact preact-render-to-string
3. Add "gatsby-plugin-preact" to gatsby-config.js

Expected result

Continue to see <meta http-equiv in head.

Actual result

Output changes to <meta httpequiv instead.

Environment

  System:
    OS: Windows 10 10.0.19042
    CPU: (20) x64 Intel(R) Core(TM) i9-10900KF CPU @ 3.70GHz
  Binaries:
    Node: 15.11.0 - C:\Program Files\nodejs\node.EXE
    npm: 7.6.1 - C:\Program Files\nodejs\npm.CMD
  Languages:
    Python: 3.9.0
  Browsers:
    Edge: Spartan (44.19041.423.0), Chromium (89.0.774.45)
  npmPackages:
    gatsby: ^3.0.1 => 3.0.3 
    gatsby-plugin-google-analytics: ^3.0.0 => 3.0.0 
    gatsby-plugin-image: ^1.0.0 => 1.0.0 
    gatsby-plugin-mdx: ^2.0.0 => 2.0.0 
    gatsby-plugin-preact: ^5.0.0 => 5.0.0 
    gatsby-plugin-react-helmet: ^4.0.0 => 4.0.0 
    gatsby-plugin-sass: ^4.0.2 => 4.0.2 
    gatsby-plugin-sharp: ^3.0.0 => 3.0.0 
    gatsby-plugin-sitemap: ^3.0.0 => 3.0.0 
    gatsby-source-filesystem: ^3.0.0 => 3.0.0 
    gatsby-transformer-remark: ^3.0.0 => 3.0.0 
    gatsby-transformer-sharp: ^3.0.0 => 3.0.0 
  npmGlobalPackages:
    gatsby-cli: 3.0.0

But this happens on netlify as well.

[Eyas]

FWIW this breaks AMP validation on Gatsby v3 preact sites (AMP requires only known tags to be set on meta, and httpequiv is invalid (only http-equiv is valid).

[LekoArts]

Hi!

I’m closing this as a stale issue as in the meantime Gatsby 4 and related packages were released. You can check our Framework Version Support Page to see which versions currently receive active support. If this is a feature request, please create a discussion as we moved feature requests from issues to GitHub Discussions.

Please try the mentioned issue on the latest version (using the next tag) and if you still see this problem, open a new bug report. It must include a minimal reproduction.

Thanks!