On some hosts https downloads in the plugin manager aren't possible.
Either github supports a (not official supported) http download option, therefor you need to refer to nodeload.github.com.
---copied from
https://www.dokuwiki.org/plugin:plugin ----
prefix the **github.com** with **nodeload.** (so you get **nodeload.github.com** ) and it will download correctly. \\
perhaps the links in the plugin it could be rewritten automatically..\\
--- [[Hans Harder]] //2012/10/18 17:22//
Confirmed, i had the same problem and i resolved it with the next url:
http://nodeload.github.com/splitbrain/dokuwiki-plugin-translation/legacy.zip/master
--- [[Xabi Ezpeleta]] //2012/11/21 11:12//
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Also developers of other projects have these issues:
https://github.com/composer/composer/issues/1285
Their url building:
https://github.com/composer/composer/blob/master/src/Composer/Downloader/ArchiveDownloader.php#L94
And here their change to fix it again:
https://github.com/composer/composer/commit/1682532b80b9a9fee1b70458f5dbac845561881e
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Indeed not official supported. Github employee reply:
https://github.com/yeoman/yeoman/issues/691#issuecomment-10046549