FIXED on macOS 10.14.3, during February 2019… Simple, details below:
Actually, the ONLY THING you NEED TO CHANGE on macOS to make "League of Legends" work OK with high-speed fiber-optic modem "Huawei HG8245Q2" giving you Wi-Fi is:
Changing the level-based firewall pre-set in the "Security" tab of the fiber-optic modem settings as follows:
…from "High" (where League of Legends doesn't work because you fail to log-in [after long time-out]),
…to "Medium" (where League of Legends works fine, playing, after logging-in OK).
(see below for details)
…NOTE: If your Mac is connected via Wi-Fi directly to the modem, you DO NOT need to change ANYTHING ELSE to get LoL to work OK (despite all the specific recommendations from Riot in the Help pages, which didn't fix this log-in fail problem on macOS)…
• NO OPENING of any specific ports, NO port forwarding, no problem,
• Firewall CAN be "on" within macOS Preferences>"Security & Privacy">"Firewall" tab settings, BLOCKING ALL incoming connections, no problem,
• Preferences>Network>Advanced button>DNS tab, "DNS Servers:" on the left column, CAN be the Google DNS (even IPv6)… 2001:4860:4860::8888, 2001:4860:4860::8844, 8.8.8.8, 8.8.4.4, no problem,
• TCP/IP tab there CAN HAVE "Configure IPv6" as "Automatically", no problem.
…"Huawei HG8245Q2" SETTING DETAILS FOUND,
in manual "ONT V300R018C10 Security Maintenance 02.pdf"
[ in page 42 of that PDF (actually labelled page "36" of the manual) ]
Download that file as ".zip" with PDF, directly from Huawei at SUPPORT PAGE LINK:
https://support.huawei.com/enterprise/en/access-network/echolife-eg8010h-pid-22464421
…Where section says: "Security Hardening and Maintenance Guide(11)"
…Actual manual checkbox: "ONT V300R018C10 Security Maintenance 02"
REFERENCE within that relevant manual:
"2.3.4.4 Principles" section…
…mentions "Level-based Firewall" subsection…
…shows "Table 2-7 Level-based firewall rules"…
…where the "Rule" details show what happens when putting "Level" as "High", "Medium", etc…
DIFFERENCE in those settings is below:
(where setting WAS, which causes League of Legends to FAIL LOGGING-IN after 13 Gig update)
"High" setting…
• Allows SPI firewall packets.
• Allows unsolicited packets sent from the LAN side to
the FTP, DNS, and HTTP ports on the WAN side.
• Allows unsolicited packets sent from the LAN side to
the HTTP port on the gateway side.
(where setting ACTUALLY makes League of Legends to WORK OK, AS INTENDED)
—> "Medium" setting…
• (same) Allows SPI firewall packets.
• (difference-out) Allows ALL unsolicited packets sent from the LAN side to
the WAN side. ("High" setting allows: FTP, DNS, and HTTP)
• (difference-out) Allows unsolicited packets sent from the LAN side to
the HTTP, ICMP, and Telnet ports on the gateway side.
("High" setting allows: only HTTP)
• (difference-in) Allows unsolicited packets sent from the WAN side to
the ICMP and ACS ports on the gateway side.
("High" setting is: none)
Leaving that here as future reference, in case others get stuck trying to log-in on macOS.
…So, again, to fix log-in failing, simply change "Security" setting on modem, from "High" to "Medium" as shown above, nothing else needs to change on macOS for "League of Legends" to work OK as normal; you can leave your Security preferences "on".
