Could be a font that is broken. You can do a file check with the SFC.exe application. You need to open a CMD prompt window as administrator. *sfc.exe /scannow * http://answers.microsoft.com/en-us/windows/wiki/windows_10-update/system-file-check-sfc-scan-and-repair-system-files/bc609315-da1f-4775-812c-695b60477a93 ---- You can right-click and select "Inspect Element" to open the builtin Inspector with this element selected. *https://developer.mozilla.org/en-US/Tools/Page_Inspector/How_to/Examine_and_edit_HTML You can check in the <b>Rules</b> tab in the right panel in the Inspector what font-family is used for selected text. You can check in the <b>Font</b> tab in the right panel in the Inspector what font is actually used because Firefox might be using a different font than specified by the website. *https://developer.mozilla.org/en-US/Tools/Page_Inspector/How_to/Edit_fonts