Search, pagination and characters

[jflash]

Hello!

When I enter a search term that contains Estonian characters such as ä, ö, ü, õ - for example, the word "käepi" - and click the search button, the search correctly displays the products that contain this word.

However, when I then change the number of products displayed on the page (for example, from 12 to 24), the page reloads and the search term in the search box changes: the letter ä is removed, so "käepi" becomes "kepi". Naturally, no products are shown anymore, because none of the products contain that word.

Virtuemart 4.6.6 (same on older 4.6 version)
Joomla 5
PHP 8.3.30