Plugin javascript resources not copied over to platform for ubuntu

Plugin javascript files, including cordova_plugins.js and contents of plugins/ directory, fail to be included in builds for ubuntu. The issue has been found using a host of different plugins (with notional ubuntu support), and will be demonstrated here using the cordova-plugin-device.

Note: the same plugins do work without issue in Android builds, and the problem may be solved with a simple manual copy, as demonstrated below.

To replicate failure:
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cordova create plugintest com.example.plugintest plugintest

cd plugintest/

cordova plugins add cordova-plugin-device --save

cordova platform add ubuntu

cordova prepare ubuntu

cordova run ubuntu --verbose --debug
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Using chromium to inspect console output and variables (entries preceded by ">" are my input to the console):

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Failed to load resource: net::ERR_FILE_NOT_FOUND 
file:///tmp/plugintest/platforms/ubuntu/native/prefix/www/cordova_plugins.js
Received Event: deviceready
> device
VM67:1 Uncaught ReferenceError: device is not defined(...)
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To fix:
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cp ./platforms/ubuntu/platform_www/cordova_plugins.js ./platforms/ubuntu/native/prefix/www/

cp -R ./platforms/ubuntu/platform_www/plugins/ ./platforms/ubuntu/native/prefix/www/

cordova run ubuntu --verbose --debug --nobuild
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(The --nobuild option is important, otherwise the copied files are destroyed). At this stage, connecting to the console shows no net::ERR_FILE_NOT_FOUND and the "device" from the plugin is present

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adding proxy for Device
Received Event: deviceready
> device
Device {available: true, platform: "Linux", version: "15.10", uuid: "

{95eabc1234-d601-7563-d35b-abc1234}

", ...}
> device.cordova
"4.3.2"
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I'm not certain whether the fix would allow building of deb packages, but is sufficient for "cordova run" commands to work correctly.

I'd appreciate any info concerning anything I may be missing/doing wrong and/or more permanent/automated fixes.

Thanks,
PatD