PVS-Studio warning V501 for Firefox

if (protocol.EqualsIgnoreCase("http") ||
    protocol.EqualsIgnoreCase("https") ||
    protocol.EqualsIgnoreCase("news") ||
    protocol.EqualsIgnoreCase("ftp") ||          <<<---
    protocol.EqualsIgnoreCase("file") ||
    protocol.EqualsIgnoreCase("javascript") ||
    protocol.EqualsIgnoreCase("ftp")) {          <<<---

This suspicious code was found in Firefox project by PVS-Studio static code analyzer.
Warning message is:
V501 There are identical sub-expressions 'protocol.EqualsIgnoreCase ("ftp")' to the left and to the right of the '||' operator. mozinlinespellwordutil.cpp 1034

PVS-Studio is a static analyzer for detecting bugs in the source code of applications written in C, C++, C++11, C++/CX. Site: http://www.viva64.com/en/pvs-studio/