Can't use loadLegacyFabricCss in SPFX 1.8

[araLT]

Category

• Question
• Typo
• Bug
• Additional article idea

Expected or Desired Behavior

According to SPFX 1.8 documentation, it is possible to add "loadLegacyFabricCss": true to web part manifest file in order to force old fabric CSS to be loaded in the page.

Observed Behavior

After adding the mentioned property ("loadLegacyFabricCss": true) to web part manifest file, execution of commands gulp serve or gulp bundle failed and after webpacking the following error message is displayed:

[15:29:01] Error - [write-manifests] Manifest validation error (./src/webparts/helloWorld/HelloWorldWebPart.manifest.json):
(#/) Data does not match any schemas from 'oneOf'
(#/) Missing required property: description
(#/) Missing required property: extensionType
(#/componentType) No enum match for: WebPart
(#/) Additional properties not allowed: loadLegacyFabricCss
(#/) Missing required property: items
(#/) Missing required property: rootComponentId

Steps to Reproduce

1. Create new spfx 1.8 project containing web part.

2. Add "loadLegacyFabricCss": true to web part manifest file. Here is Example of such manifest file:
   

3. Run command gulp serve or gulp bundle and you will get the mentioned error:
   

[msft-github-bot]

Thank you for reporting this issue. We will be triaging your incoming issue as soon as possible.

[patmill]

Thank you to @srideshpande for finding a temporary solution. The final one will require an update to our public packages.

Go to the below location

node_modules\@microsoft\sp-module-interfaces\lib\manifestSchemas\jsonSchemas\client-side-web-part-manifest.schema.json

Add the following line to the file before the 'canUpdateConfiguration' entry

 "loadLegacyFabricCss": { "$ref": "any-value.schema.json" }

save, and run gulp or gulp build or gulp bundle or gulp --ship.

[abhishek-raj]

@patmill Is this fixed yet? I am facing the same issue when I used it yesterday.

@araLT Can you reopen the bug as it is not fixed yet and the temporary solution would not work in build pipelines?

For now, I am just including the fabric css file directly using require('../../../../node_modules/office-ui-fabric-core/dist/css/fabric.min.css'); till this is fixed.

[salahsaleh]

@patmill is this fixed yet?

I am also facing same issue but with another property 'supportedHosts:["SharePointWebPart","TeamsTab"]'

When I am passing this values in manifiest file of project I am getting error.

[VesaJuvonen]

Fixed with the v1.8.1 release - see release notes at - https://github.com/SharePoint/sp-dev-docs/wiki/SharePoint-Framework-v1.8.1-release-notes

[msft-github-bot]

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