Bowman's hack also added to MediaWiki:Common.js at svwp as well, and with success. Don't understand the MediaWiki:Group-user.js comment; shouldn’t anonymous users have alphabetical (short) lists as well? Is there an overhead to take into account?

Correction: after emptying of the browser cache, restart and start at a different wiki, I get other graph stats to begin with. So indeed it seems to be a caching issue. :-)

Thanks for the interest to solve this (bug). But my experience is: whatever wiki I search stats for, my home wiki (svwp) is still there in the yearly and monthly graphs. Eg. I cannot find a way to see the graphs data for neither the enwp stats, nor any other wiki I contribute to. All the stats in numbers (outside the graph) seem correct, though. So maybe it's more than just a caching issue? Best of wishes/Per

Yes, to me it still happens <s>90</s> 95 percent of the time with some older browsers, and less than <s>50</s> 60 percent of the time with newer and updated browsers. It's mostly when restarting browser or computer or when waking up computer. And sometimes right within an active editing session (which is quite remarkable but may be network related?).

Well, normally, when I'm logged out, it doesn't matter what WMF project I start with as I'm then logged out everywhere. Logging in anywhere generally gets me logged in everywhere. So a general Wikimedia cookie seems to take care of that.

Maybe. This happens to me quite often, and in various situations. E.g. both when saving after a long time since last save and saving within minutes after last save, for no apparent reason. It resembles the kind of behaviour where the logging out can happen a long time after last save and shortly after a last save. Lately (last two weeks) the logging out and need to log in after a browser restart has been almost mandatory, in both my major browsers (Camino and Chrome) and on both my computers, over both fixed line and wifi connection. Maybe my using both the OS X firewall (incoming connections) and Little Snitch firewall (outgoing connections) can be related?

Thanks for getting back to me. Just as if poking fun to me, the web cookies for Google Chrome and Mozilla Firefox seem to work right now (at both computers). Still those for Safari (5.1.10 under MOS X 10.6.8 and 6.2.4 under 10.8.5) and Camino (both under 10.6.8 and 10.8.5) are gone. I know Camino is a lost cause (not being updated anymore), but this browser is still the only browser under OS X with single key invoking the access keys in key shortcut combos (https://en.wikipedia.org/wiki/Wikipedia:Keyboard_shortcuts); so far I'm at 300 percent more efficient in my Wikipedia editing using Camino. And still both versions of Safari have the same problem.