CCleaner Browser cannot show site hxxps://opistopalvelut.fi/sipoo/
Version 92.0.11264.134 (Official Build) (64-bit)
Seems to load fine for me and, at a glance at least, seems to render the same as in any other browser:
... although I may be a point release ahead: Version 92.1.11422.134 (Official Build) (beta) (64-bit).
When you say "cannot show", is the page rendering strangely, or failing to load? Can you provide a screenshot?