fix(theme): add clipboard fallback for non-HTTPS environments

[io-ing]

navigator.clipboard is undefined in non-HTTPS contexts (e.g. accessing dev server via LAN IP like http://192.168.x.x:3000), which causes the copy button to throw an error since #11422 removed the copy-text-to-clipboard fallback.

This PR adds a textarea-based fallback when navigator.clipboard is unavailable.

Fixes 11791

[meta-cla]

Hi @io-ing!

Thank you for your pull request and welcome to our community.

Action Required

In order to merge any pull request (code, docs, etc.), we require contributors to sign our Contributor License Agreement, and we don't seem to have one on file for you.

Process

In order for us to review and merge your suggested changes, please sign at https://code.facebook.com/cla. If you are contributing on behalf of someone else (eg your employer), the individual CLA may not be sufficient and your employer may need to sign the corporate CLA.

Once the CLA is signed, our tooling will perform checks and validations. Afterwards, the pull request will be tagged with CLA signed. The tagging process may take up to 1 hour after signing. Please give it that time before contacting us about it.

If you have received this in error or have any questions, please contact us at cla@meta.com. Thanks!

[netlify]

✅ [V2]

Built without sensitive environment variables

Name	Link
🔨 Latest commit	0e17ed4
🔍 Latest deploy log	https://app.netlify.com/projects/docusaurus-2/deploys/69b020f35753250008ef7c51
😎 Deploy Preview	https://deploy-preview-11792--docusaurus-2.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify project configuration.

[slorber]

I would prefer re-introducing copy-text-to-clipboard
because it handles quirks we don't want to deal with

We could eventually lazy load it with a dynamic import so that it doesn't need to load/init for users who are using https

[slorber]

If this doesn't work, I'd rather revert to the former lib we were using, that handles quirks too

[meta-cla]

Thank you for signing our Contributor License Agreement. We can now accept your code for this (and any) Meta Open Source project. Thanks!

[socket-security]

Review the following changes in direct dependencies. Learn more about Socket for GitHub.

Diff	Package	Supply Chain Security	Vulnerability	Quality	Maintenance	License
	rimraf@​3.0.2
	eslint@​8.57.1
	postinstall-postinstall@​2.1.0
	jest-environment-jsdom@​30.2.0
	@​types/​detect-port@​1.3.5
	jest@​30.2.0
	@​types/​update-notifier@​6.0.8
	recma-mdx-displayname@​0.4.1
	@​typescript-eslint/​parser@​5.62.0
	@​types/​prompts@​2.4.9
	@​types/​color@​3.0.6
	@​babel/​preset-react@​7.27.1 ⏵ 7.25.9
	@​types/​webpack-bundle-analyzer@​4.7.0
	eslint-config-prettier@​8.10.0
	@​swc/​core@​1.7.39
	@​types/​serve-handler@​6.1.4
	@​babel/​preset-typescript@​7.27.1 ⏵ 7.25.9				+2
	@​ai-sdk/​react@​2.0.76 ⏵ 2.0.133			+1
	workbox-routing@​7.1.0
	@​argos-ci/​playwright@​2.0.0
	workbox-strategies@​7.1.0
	strip-ansi@​6.0.1
	@​babel/​plugin-transform-runtime@​7.28.3 ⏵ 7.25.9
	@​types/​semver@​7.5.8
	@​types/​fs-extra@​9.0.13
	@​types/​react-dom@​19.2.3
	@​types/​shelljs@​0.8.15
	npm-run-all@​4.1.5
	raw-loader@​4.0.2
	eslint-plugin-header@​3.1.1
	lodash@​4.17.21 ⏵ 4.17.23	+1	+2	+1
	netlify-plugin-cache@​1.0.3
	jest-serializer-react-helmet-async@​1.0.21
See 79 more rows in the dashboard

View full report