bug: ErrorException: Deprecated: strcasecmp(): Passing null to parameter #2 ($string2) of type string is deprecated

[sentry]

Sentry Issue: KEYMAN-COM-4H4

ErrorException: Deprecated: strcasecmp(): Passing null to parameter #2 ($string2) of type string is deprecated
  File "/includes/ui/keyboard-details.php", line 705, in UI\KeyboardDetails::{closure:UI\KeyboardDetails::WriteKeyboardDetails():684}
    (!strcasecmp($bcp47, self::$bcp47) ? "<mark>".htmlspecialchars($detail->languageName)."</mark>" : htmlspecialchars($detail->languageName)).
  File "/includes/ui/keyboard-details.php", line 713, in UI\KeyboardDetails::WriteKeyboardDetails
    })();
  File "/includes/ui/keyboard-details.php", line 83, in UI\KeyboardDetails::render_keyboard_details
    self::WriteKeyboardDetails();
  File "/keyboard.php", line 42
    \UI\KeyboardDetails::render_keyboard_details($id, 'stable', false, $bcp47);