@baris Thanks for the heads-up, v0.5.12 has been deprecated for the version mismatch issue, so v0.5.11 should be the recommended version
Category meta description using languages
For setting category name and description in many languages, you can use:
[[category:categoryName1]] and [[category:categoryDescription1]]
And then your categories will have a different name and description for every lang. That is OK.
Problem is with meta description on viewing category:
<meta name="description" content="&lsqb;&lsqb;category:categoryName1&rsqb;&rsqb;" />
Can you open an issue here https://github.com/NodeBB/NodeBB/issues