Yes, this is under investigation
It could be any page, such as live, daily, etc. It is only the first connection that requires login, after that all is normal for a time until I restart the browser. I use Firefox mostly but get the same result with other browsers such as Opera. I usually use address https://www.pvoutput.org/intraday.jsp?sid=1234.
I also have been checking another system, same address format but different sid with the same observations. I use an Android tablet as well as Windows PC, all behave the same.
My cookies are permanent (i.e. not deleted), that have persistence until they expire. I can fudge/avoid login by clicking on my link which will bring up the login page, then close that tab. Clicking on the link a second time will bring up the page without having to log in.
This is the expected behaviour, once you are logged in the page should display as normal.
Unfortunately, one cannot send a link to someone, and have them view it unless they have set up an account first and logged in. The view only option has gone.
I have my summary page open
The behavior is this (updated after some testing what happens):
When I open pvoutput.org in a fresh browser window, I need to login so that is fine
Then I go to my summary page, which has an id and my sid as querystring parameters
I leave the browser tab open, switch to other open browser tabs to look there
When I later (this might be a next day or even after 30 minutes or so) go back to the browser tab with my summary page and hit the refresh button, I am redirected to the https://pvoutput.org/login.jsp page
There I remove the /login.jsp part of the url and hit enter
Then I get redirected to the summary page again, without the need to log in
When I hit refresh directly after this, the summary page keeps showing without the annoying redirect to the login.jsp page.
But after 30 minutes or so not having touched the page, the whole cycle starts over again with being redirected to the login.jsp page etc.
As I mentioned the browser will still have a valid auth cookie in its cache so that’s why you don’t need to login again
But you are totally unnecessary redirected to the login page once in a while
I figure that something is built into page request that make logged in users getting redirected to the login.jsp page after some time of inactivity e.g. a cookie with a short expiry time that needs to get refreshed.
As Oldtech said, this might work for any page you can access where a log in is required
I did not check that myself