JS (?) Breaks When Loading Many Posts on List Screen

When I navigate to All Posts, certain functionality breaks if my Screen Options are set to display too many posts. I’m unable to click on Screen Options or Quick Edit (all that happens is that a hashtag gets added the URL).

When I discovered this yesterday, I tried loading just the Drafts (there are only 6), but still all that functionality wouldn’t work. Here is the troubleshooting I did:

-I use Firefox (latest version always) but also tested this on Chrome and IE (also both at the latest version). Same thing everywhere.

-I loaded the All Pages screen and everything works fine there (49 pages total). Same with CPTs, no problem.

-I signed out of the website, cleared the browser cache, and flushed the cache of my caching plugin. No effect.

-I deactivated the plugins I thought could be affecting the post list screen, Easy Filter and Admin Columns. No change (and much uglier).

-I also deactivated Better WP Minify, since I thought perhaps it was affecting the necessary scripts. Still no change!!!

-I checked the scripts I’ve added manually as well as those I’ve deregistered myself, and everything looks good to me. (NB: I’m using a custom theme based on Underscores.)

-I turned on debug in the wp-config file and checked the Error Console in the browser — it didn’t display any errors. I reloaded the page again with the Error Console on, and still no errors…

-I tried, as per some older threads, to turn off javascript concatenation in wp-config, but still no change.

-I installed Query Monitor to see if it could help, but unfortunately, it seems to rely on the same functionality to work on admin screens, so I wasn’t able to find out much, but it did indicate that the page was timing out.

-I tried to figure out if there was a way to change the number of posts per page without going through Screen Options, took a look at the Options Table, Googled it, but wasn’t able to find anything useful.

After spending most of yesterday on this, I decided to put it aside for the time being. Now today, for no reason at all that I can tell, it works when I visit Drafts!

So, I was able to change the number of posts listed in Screen Options. My setting was 160 posts per page. I changed it to 125 but things still didn’t work in All Posts. I returned to the Drafts to change the Screen Options, next trying 100 posts per page, but it still didn’t work. I then tried 50 posts per page, which works.

To make sure that everything actually does work as expected, I reactivated Admin Columns, Easy Filter, and Better WP Minify, double-checked all the settings, then visited the All Posts screen again. Everything still worked. I also checked Chrome and IE to make sure, and it’s all good.

So great, the problem is sort of fixed — so long as I don’t increase the number of posts displayed per page. But I’m sure this is a bug of some kind since it is clearly related to the timeout issue. That seemed strange to me since I have define('WP_MEMORY_LIMIT', '400M'); in my wp-config file…

I’m not sure if this is the right place to report this issue — but I’m also hoping to find out if there’s a way to increase the number of posts displayed per page on the All Posts screen without affecting the Quick Edit and Screen Options functionality. Many thanks in advance for suggestions!