Same issue with an Archer CR700 (hardware version V1.1, firmware version v1.1.0 Build 20160812 Rel515810). Firefox and Safari oare both reporting a syntax error on line 39 of index.htm:

22:08:51.309 SyntaxError: missing } after property list 1 index.htm:39:18
.script http://192.168.1.1/js/lib.js:255:4
.dhtml/< http://192.168.1.1/js/lib.js:223:1
.each http://192.168.1.1/js/jquery-1.8.3.min.js:2:14541
.dhtml http://192.168.1.1/js/lib.js:222:3
.appendElem http://192.168.1.1/js/lib.js:230:4
.fill http://192.168.1.1/js/lib.js:513:3
.tpLoad/< http://192.168.1.1/js/lib.js:502:6
.io/<.success http://192.168.1.1/js/lib.js:372:38
.tpAjax/onreadystatechange http://192.168.1.1/js/lib.js:303:7

In my case, the problem is that the script inserted into the head of the document does not correctly escape the names of the hosts in the embedded rules object. Earlier today, I set up time limits for a host with a single quote in its name. That broke the quoting in the ruleList dictionary:

[/FONT][FONT=courier new]var ruleList = [ {internalHostRef: 'TheHostRef',
ruleName: 'John's desktop',
enable: 1},];

I'll try a factory reset later to see if that removes the rule. I'll have to redo my wireless network settings as well, which is sort of a pain.