[SOLVED] Meta tag with dot in key is not recognized

Microsoft would like to find this tag in my <head> part:

<meta name="msvalidate.01" content="5..............................Z" />

So I write:

page.meta {
  msvalidate.01 = 5..............................Z
}

However that tag appears only if I remove the dot.

I also tried

page.meta {
  ["msvalidate.01"] = 5..............................Z
}

This does not help.

Can I help by reporting this as bug, or is there another solution to this?

Edit 5.1.23 13:54 TYPO3 Version 11.5

You need to escape the dot:

page {
  meta {
    msvalidate\.01 = 5..............................Z
  }
}