UserAgent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.113 Safari/537.36

Steps to reproduce the problem:
1. run chromium
2. work for a few hours using multiple tabs; maybe 5 demanding ones
3. system either slow or hung to the point of needing reboot

What is the expected behavior?
linux top command shows plenty of RAM so I suspect some other sort of resource leak, but the hard drive often spins incessantly. If I manage to close tabs(sometimes can't) it may manage to run a bit longer, but system croaks on a regular basis; more than once daily.

What went wrong?
one repetitive message when run from command line:
tim@rover:~$ chromium
[5078:5110:0927/191947:ERROR:nss_util.cc(809)] After loading Root Certs, loaded==false: NSS error code: -8018

but I could find no such error documented. System either requires power cycle because OS is unresponsive, or sometimes if caught early can close chromium and restart chromium and apparently clean again. I believe this is common to both chrome and to chromium for I've switched over to chromium due to the unusability of chrome, but similar results are occurring.

Did this work before? N/A 

Chrome version: 53.0.2785.113  Channel: n/a
OS Version: debian testing
Flash Version: Shockwave Flash 22.0 r0

Difficulty diagnosing bug due to unresponsive system, often including other apps and the OS, but when it begins and I have top running RAM appears to be available even though this bug acts like its running out of RAM. I once even had my hard drive light coming on at each keypress which made me think I was hacked, but you likely know how that goes.