This is the first maintenance release of Wireshark 2.6. The repository will bring you to version 2.6.3 automatically.
If you haven’t already added the 1310nm.net Wireshark repository, follow the instructions in Wireshark on CentOS7 (TL;DR version). Run
yum update to get the latest repository information, and upgrade to the most recent Wireshark version.
libnghttp2for HTTP/2 support.
yum install epel-releaseprior to installing Wireshark will help here.