Active job logs not displayed

When I open the log for a job still in progress, it does not display any output which was logged before I opened the page. For example, I might see a log like this shortly after I open the page:

20 output line 3/7
21 output line 4/7
22 output line 5/7

and once the job has finished, if I refresh the page, I can see

1 ▶ Run command
18 output line 1/7
19 output line 2/7
20 ...

Is there any way to view the earlier logs short of opening the page sooner or opening the raw logs? Why doesn’t the full log display in the UI?