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Windows: Is it possible to optimize space usage, when both Mozilla Firefox and Thunderbird are installed? I see that some files are the same in both applications (mostly common DLL libraries) - even 10 MB


I think that the best idea is to add one folder: Mozilla shared, just for all shared libraries.

Additional System Details

Installed Plug-ins

  • Shockwave Flash 11.1 r102
  • Adobe PDF Plug-In For Firefox and Netscape 10.1.2
  • 5.0.61118.0
  • NPRuntime Script Plug-in Library for Java(TM) Deploy
  • Next Generation Java Plug-in 10.2.1 for Mozilla browsers
  • Version 1.1.11, copyright 1996-2011 The VideoLAN Teamhttp://www.videolan.org/
  • np-mswmp


  • User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:11.0) Gecko/20100101 Firefox/11.0

More Information

Tom Farrow 10 solutions 100 answers

Sorry, not really. If you give me some details on exactly what you want, I'll file a feature request bug in our bug tracker for you, if you'd like that.

Question owner

Hm.. it is nothing critical. Not a bug, error nor mistake. Just my idea. Just thought about it as in similar applications: All Open Office software use shared libs, Microsoft Office too.

And it could keep both Firefox and Thunderbird up to date. Now both applications update seperately, and many files (compressed, but still) are downloaded two times. The biggest files: d3dx9_43.dll, D3DCompiler_43.dll, mozjs.dll but there are many others.

You should decide if it is worth to show my sugestion..

Tom Farrow 10 solutions 100 answers

Okay. I'll put a bug in so developers can see if this could be made somehow. We could publish it as a lite suite

Question owner

Thank you for your time, have a nice weekend !

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10761 solutions 96861 answers

You would have to update both (all) versions at the same time to avoid inconsistencies between the DLL versions that the programs use.
It would even be more difficult if you install multiple versions of Firefox or Thunderbird for testing purposes.