When adding filters to the event list, at some point the HTTP parser starts failing. This results in a blank page, and the message

WARN [qtp423651526-541] o.e.j.h.HttpParser: HttpParser Full for SCEP@b87c728{l(/<client IP>:17195)<->r(/<server IP>:8980),s=1,open=true,ishut=false,oshut=false,rb=false,wb=false,w=true,i=1r}-{AsyncHttpConnection@29358ff2,g=HttpGenerator{s=0,h=-1,b=-1,c=-1},p=HttpParser{s=-1,l=15,c=-3},r=11}

in web.log