Persistent 'Error Plugin "xyz" failed to install' problems during build [WORKAROUND]
If you are seeing errors like the following, where a plugin fails to install each time you perform a build, the workaround described in this post may resolve your issue.
This workaround ONLY applies if you have successfully added the problem plugin to your project AND it exists within the plugins directory inside your project directory. There are other reasons for the above failures, so applying this workaround is NOT a guarantee that it will resolve your issue.
If a copy of the problem plugin is present in the plugins directory, inside of your project folder, edit the README.md file inside of that problem plugin. It doesn't matter what you add to the README.md file, just add a line of text like "I'm trying to fix a build problem" inside that file so the plugin will appear to the XDK to have been changed.
Note that if you re-add the problem plugin to your project this issue may return, in which case you'll need to reapply this workaround.
The workaround forces the XDK and the build system to use the plugin that is located in your project directory, rather than relying on the NPM registry to retrieve it for building your app. A future release of the XDK and build system will lessen this dependency on the NPM registry for builds (the XDK will still depend on the NPM registry and GitHub to add plugins to your project folder when using the plugin management tool).