Localising FossaMail Lightning

[Antonius32]

Problem: FossaMail Lightning is currently only available in American English (en-US).

Solution: download the multi-lingual Mozilla Lightning add-on, extract the .jar files for your language and add them to FossaMail Lightning:

1) Open the downloaded "lightning-2.6.5-sm+tb-windows.xpi" file with your preferred archiver (like 7-Zip, WinZip or WinRAR).
2) Navigate to "lightning-2.6.5-sm+tb-windows.xpi\chrome" and find the "calendar-[xx].jar" and "lightning-[xx].jar" files for your language (and region).
3) Extract both .jar files to a convenient location (Desktop, for example)
4) Find the "lightning-24.5.0.win32.xpi" file (or the "lightning-24.5.0.win64.xpi" file for 64-bit FossaMail), or download it from the FossaMail website if you haven't already.
5) Extract it's contents to a convenient location ("Desktop\lightning-24.5.0.win32", for example).
6) Either cut & paste or copy & paste the .jar files you extracted in step 3 to "Desktop\lightning-24.5.0.win32\chrome" (or "Desktop\lightning-24.5.0.win64\chrome").
7) Move up one folder, so you're back in "Desktop\lightning-24.5.0.win32" (or "Desktop\lightning-24.5.0.win64").
8) Open the "chrome.manifest" file with a text editor (Notepad, for example). Click on Edit->Replace, search for "en-US" an replace it with your language (and region), in my case: "nl". Close your text editor and when prompted, click "Save changes".
9) Highlight the contents of your "Desktop\lightning-24.5.0.win32" (or "Desktop\lightning-24.5.0.win64") folder, right-click them and add them to a zip archive with your preferred archiver. Choose a suitable name for the archive, in my case: "lightning-24.5.0.win32_nl.zip".
10) Finally, change the extension for the created archive to ".xpi", which, in my case, results in a file named "lightning-24.5.0.win32_nl.xpi".

That's it! You have localised FossaMail Lightning to your language, and your .xpi file is now ready for installation to FossaMail.

* You can also add the .jar files for your language to FossaMail Lightning when it's already installed to your profile: just navigate to "C:\Users\[Your name]\AppData\Roaming\FossaMail\[random-name].default\extensions\{e2fda1a4-762b-4020-b5ad-a41df1933103}\Chrome" and copy your extracted .jar-files to this location. Then move up one folder to the "{e2fda1a4-762b-4020-b5ad-a41df1933103}" directory, open "chrome.manifest" and edit it as described above.

I successfully localised FossaMail Lightning to "Dutch" with this method. I thought I'd post my solution here; maybe it will help other users who wish to localise FossaMail Lightning to their preferred language. I have attached my Dutch .xpi file (32-bit) for reference, or for other Dutch users, who can simply download and install it.