Unicode character in Page link trips source editor

[rsw]

Hello,

I have created a page with a leading unicode character, such as "📝 Page title".

I have linked to that 📝page from a main page. When I try to source edit the main page, the source editor always reports an error upon apply:

Error validating source

• Character reference "&#55357" is an invalid XML character. (400)
• Line : 177, Column : 52

Line 177:

<ac:link>
  <ri:page ri:content-title="&#55357;&#56541; Page title"/>
  <ac:plain-text-link-body><![CDATA[Page title]]></ac:plain-text-link-body>
</ac:link>

 Is this a known issue?

TIA

[rsw]

anyone?