Hmmm… opening the devloper console I just see a lots of entries to admin-ajax.php and the “enable all updates” never completes, the spinner just keeps spinning…
Do you want me to paste in the responses from the developer console?
Here are the request headers
>>>
Host: abc.com
User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:58.0) Gecko/20100101 Firefox/58.0
Accept: application/json, text/javascript, */*; q=0.01
Accept-Language: en-GB,en;q=0.5
Accept-Encoding: gzip, deflate, br
Referer: https://abc.com/wp-admin/index.php?page=mpsum-update-options
Content-Type: application/x-www-form-urlencoded; charset=UTF-8
X-Requested-With: XMLHttpRequest
Content-Length: 136
Cookie: autoptimize_feed=1; wordpress_sec_d86a57514299352a4bee831bd82c133a=admin-abc%7C1521464214%7Cm9hSqG8aYiCi3qCAO4kzM8TNjAnUNA5nNGThJQe945G%7C0dfdfe6da1db92991ae739daa82ce5b9b588f363086d39eea6e8f08eef3c3e9e; __cfduid=d95baa38bc37c0e66d0ae74aab28803e91515412921; gadwp_wg_default_metric=referrers; gadwp_wg_default_dimension=7daysAgo; gadwp_wg_default_swmetric=sessions; _ga=GA1.2.amp-EDDv8YtoXCGcW_RpW32kZg; wp_affiliates=eccbc87e4b5ce2fe28308fd9f2a7baf3; _h_affiliates=c6003dbcf7c48a121d5f02d668a679abf36b58022e41718299eec3e3d005c58c; spu_box_448=true; wordpress_logged_in_d86a57514299352a4bee831bd82c133a=abc%7C1521464214%7Cm9hSqG8aYiCi3qCAO4kzM8TNjAnUNA5nNGThJQe945G%7C0c70367b1f3ee386474f4f92e6141ad2f528bfd0b19ed71d1b496bc887dd19ac; wp-settings-1=libraryContent%3Dbrowse%26editor%3Dhtml%26hidetb%3D1%26imgsize%3Dlarge%26align%3Dleft%26advImgDetails%3Dshow; wp-settings-time-1=1520254615; wordpress_test_cookie=WP+Cookie+check; mtc_id=10; mtc_sid=11d3a6a623bc2ad508ff1e6d45754792d7893521; PHPSESSID=92cab2c0l2bbdc1p5idn0h7pn4
DNT: 1
Connection: keep-alive
<<<
And here are the response headers
>>>
Server: nginx
Date: Mon, 12 Mar 2018 05:58:30 GMT
Content-Type: application/json; charset=UTF-8
Content-Length: 48
Connection: keep-alive
Keep-Alive: timeout=60
Expires: Wed, 11 Jan 1984 05:00:00 GMT
Cache-Control: no-cache, must-revalidate, max-age=0
Pragma: no-cache
X-Robots-Tag: noindex
X-Content-Type-Options: nosniff
X-Frame-Options: SAMEORIGIN
Referrer-Policy: same-origin
<<<
Does this help?