Issue with canvas

[sajrashid]

Description

Same as this issue #17661 with canvas

Describe the issue that you're seeing.

6:25:38 AM: success Building production JavaScript and CSS bundles - 37.833s
6:25:38 AM: success Rewriting compilation hashes - 0.012s
6:25:45 AM: error Generating SSR bundle failed
6:25:45 AM: Unexpected character '�' (1:0)
6:25:45 AM: not finished Generating image thumbnails - 55.522s
6:25:45 AM: not finished Building static HTML for pages - 7.013s
6:25:45 AM: error Command failed with exit code 1.

tried the suggested changes in gatsby-node.js, the issue happens when creating a production release

Steps to reproduce

Clear steps describing how to reproduce the issue.
try "build": "gatsby build" from this repo
https://github.com/sajrashid/docsSite
you can also see the issue here on netlify

How to Make a Minimal Reproduction: https://www.gatsbyjs.com/contributing/how-to-make-a-reproducible-test-case/

Run gatsby info --clipboard in your project directory and paste the output

Binaries:
   Node: 16.4.0 - C:\Program Files\nodejs\node.EXE    Yarn: 1.22.10 - ~\AppData\Roaming\npm\yarn.CMD 
   npm: 7.17.0 - C:\Program Files\nodejs\npm.CMD  
 Languages:
   Python: 3.9.5 - /c/Python39/python
 Browsers:
   Edge: Spartan (44.19041.1023.0), Chromium      
(91.0.864.59)
 npmPackages:
   gatsby: ^2.26.1 => 2.26.1
   gatsby-image: ^2.10.0 => 2.10.0
   gatsby-plugin-sharp: ^2.13.4 => 2.13.4
   gatsby-remark-embed-snippet: ^6.5.0 => 6.5.0   
   gatsby-remark-embedder: ^5.0.0 => 5.0.0        
   gatsby-remark-highlight-code: ^3.0.0 => 3.0.0  
   gatsby-remark-prismjs: ^5.5.0 => 5.5.0
   gatsby-source-filesystem: ^2.10.0 => 2.10.0    
   gatsby-transformer-remark: ^2.15.0 => 2.15.0   
   gatsby-transformer-sharp: ^2.11.0 => 2.11.0    
 npmGlobalPackages:
   gatsby-cli: 3.8.0

Also name any flags you use inside gatsby-config.js.
not sure can't see anything called flags

[LekoArts]

Your onCreateWebpackConfig call is inside the createPages API call. https://github.com/sajrashid/docsSite/blob/0d611f67f6b2ded02c53b5dfc38deca863fbccb1/gatsby-node.js#L25-L56

You need to place this at the top level.

[sajrashid]

oops very sorry, my bad

I've moved it out and deployed it fails with the same :

direct link to my gastby-node.js file

8:36:58 AM: error Generating SSR bundle failed
8:36:58 AM: Unexpected character '�' (1:0)

build log

[sajrashid]

the example I pasted contained "develop-html" changed to "build-html" and it's working fine.. thanks

[sajrashid]

ensure if (stage === "build-html") { & not "develop-html"