Observation Details
The page title is "Vertragsverlängerung für Mobilfunkkunden | Telekom". While no failure of the success criterion, improvements are possible:
Page part "Vertragsverlängerung für Mobilfunkkunden" does not directly match the main page heading; if e.g. there is another "Vertragsverlängerung für ..." for something else, this should also be reflected in the main page heading
The vertical bar "|" sometimes is announced by assistive technology as "vertical bar"; using other symbols, usually not announced, could improve the page title even more
Remediation Notes
Replacing the vertical bar with a character, usually not announced by a screen reader. E.g.:
, – comma
… – ellipses typed as …
› – caret written as ›