[SPFx 1.22.1] Placeholder {tenantdomain} was found in serve.json warning message even though it doesn't exist

[kbeverforden]

Target SharePoint environment

SharePoint Online

What SharePoint development model, framework, SDK or API is this about?

💥 SharePoint Framework

Developer environment

None

What browser(s) / client(s) have you tested

• 💥 Internet Explorer
• 💥 Microsoft Edge
• 💥 Google Chrome
• 💥 FireFox
• 💥 Safari
• mobile (iOS/iPadOS)
• mobile (Android)
• not applicable
• other (enter in the "Additional environment details" area below)

Additional environment details

No response

Describe the bug / error

I have updated serve.json but I still see this warning when I run heft start

[build:configure-webpack-serve] Placeholder {tenantdomain} was found in serve.json but OS variable SPFX_SERVE_TENANT_DOMAIN is not set. Either set the environment variable or update the serve.json initial page url.

The "heft start" alias was expanded to "heft build-watch --serve".

Starting incremental build...
 ---- build started ---- 
[build:set-browserslist-ignore-old-data-env-var] Setting environment variable BROWSERSLIST_IGNORE_OLD_DATA=1
[build:sass] Generating sass typings...
[build:copy-javascript] Copied 10 files and linked 0 files
[build:sass] Generated sass typings
[build:typescript] Using TypeScript version 5.8.3
[build:typescript] Starting compilation in watch mode...
[build:typescript] Found 0 errors. Watching for file changes.
[build:typescript] Copied 156 files and linked 0 files
[build:lint] Linting isn't currently supported in watch mode
[build:configure-webpack-serve] Placeholder {tenantdomain} was found in serve.json but OS variable SPFX_SERVE_TENANT_DOMAIN is not set. Either set the environment variable or update the serve.json initial page url.
[build:configure-webpack-serve] Launching initial page: https://xxxxxx.sharepoint.com/sites/ClientPortalQA/_layouts/15/workbench.aspx?debugManifestsFile=https%3A%2F%2Flocalhost%3A4321%2Ftemp%2Fbuild%2Fmanifests.js&debug=true&noredir=true
Webpack patch plugin applying 1 patch file(s)
Applying QA settings to webpack
[build:webpack] Using Webpack version 5.103.0
[build:webpack] Starting webpack-dev-server
<i> [webpack-dev-server] Project is running at:
<i> [webpack-dev-server] Loopback: https://localhost:4321/, https://[::1]:4321/
[build:webpack] Started Webpack Dev Server at https://[::1]:4321/
[build:webpack] Running incremental Webpack compilation
[build:configure-webpack-serve] 
[build:configure-webpack-serve]  ╔═══════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════╗
[build:configure-webpack-serve]  ║                                                                 To load your scripts, use this query string:                                                                  ║
[build:configure-webpack-serve]  ║                                   ?debugManifestsFile=https%3A%2F%2Flocalhost%3A4321%2Ftemp%2Fbuild%2Fmanifests.js&debug=true&noredir=true                                    ║
[build:configure-webpack-serve]  ╚═══════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════╝
[build:configure-webpack-serve]
webpack 5.103.0 compiled successfully in 17372 ms
 ---- build finished (46.793s) ---- 
-------------------- Finished (46.815s) --------------------
Waiting for changes. Press CTRL + C to exit...

serve.json (replaced my company name with xxxxxxx in this ticket for privacy)

{
    "$schema": "https://developer.microsoft.com/json-schemas/spfx-build/spfx-serve.schema.json",
    "port": 4321,
    "https": true,
    "initialPage": "https://xxxxxx.sharepoint.com/sites/ClientPortalQA/_layouts/15/workbench.aspx?debug=true&noredir=true&debugManifestsFile=https://localhost:4321/temp/build/manifests.js"
}

Steps to reproduce

Run heft start after updating serve.json

Expected behavior

Warning message about {tenantdomain} should not be visible.

[Ashlesha-MSFT]

Hello @kbeverforden,
Thank you for bringing this issue to our attention. We will look into it and get back to you shortly.
If you don’t receive a reply within two working days, please use this escalation form to escalate.

[Ashlesha-MSFT]

@kbeverforden,
We were able to reproduce the issue, and we are investigating it. We have logged this as a bug, and our engineering team will look into it.
Thank you!
Placeholder {tenantdomain} was found in serve.json but OS variable SPFX_SERVE_TENANT_DOMAIN is not set. Either set the environment variable or update the serve.json initial page url.