WPMU conflicting with WordPress 4.6 + various Plugins

I have had extremely bad experiences with WPMU. I've installed Dashboard, Smush Pro and Hummingbird on several pages.
Shortly after installing Hummingbird, I had problems on some of the pages, wherefore I deactiveted Hummingbird.
Trying to update to WordPress 4.6 was not possible before I deactivated WPMU !!!

Finally, I use Gravity Forms on some of the websites. On one website, for a company having at least 20-25 filled in forms every day, WPMU collapsed one of the forms.

How do I know it's due to WPMU?
For the simple reason, that by disabling WPMU, everythng worked again.

I have not tried only to use Smush Pro withour Dashboard, in order to see if that is ok.
I want to use Smush Pro, but I cannot take the risk again, I'm afraid.

There must a lot of other people having similar problems.
Are you in fact looking in to the problem, and if so, do you have a solution?

I want to know before I take a final decission whether to cancel my membership.

Thanks,

Jorgen

P.S. I did search on Google, and can see previous problem in 2013 with Gravity Form, but it seems there are still problems.

    Michelle Shull

    Hi there, Jorgen!

    Sorry to hear you're having issues. I tested the 4.6 update with our plugins, and I was able to update without issue. I'd be happy to help sort out your issue, but I'm going to need more information.

    You say "WPMU" collapsed one of your forms. Which plugin caused the issue, and what do you mean by collapse? Was the form minimized on the page, or perhaps hidden in some way?

    "Shortly after installing Hummingbird, I had problems on some of the pages, "
    What problems did you have?

    I took a look at your history, since you mention you've had lots of issues, but I see this is the first support ticket you've opened with us. We're always happy to help sort out issues. We'd love to help if you can give us some more specific details. Since I haven't seen a lot of similar issues reported, it sounds like maybe there's a conflict with a theme or another plugin that's causing some issues for you.

    Let's start by making sure you've got the right plugin as a culprit. Start by turning off all your plugins and switching to a default WP theme. (Like 2014 or 2016.) Turn on the WPMU dev product you think is causing the issue. Keep turning on plugins until you see the issue again, and make a note of what happened. If the plugins all check out, switch back to your regular theme and see if that allows you to reproduce the issues.

    As for the Gravity Forms issue, I'm sure we can help you out with a quick CSS fix to make the form display correctly. We just need to know exactly what's happening, so we can track down the source. A screenshot could help, or you could grant support access for us to log in and take a look. (You'll need our dashboard installed to do this, then go to the Support tab, then click enable.) Be sure to point us to a place where we can see the issue in action.

    We're more than happy to help you sort this out, you came to the right place.

    Jorgen Uhlig

    Hello Michelle,
    Thanks very much for your reply, and sorry for not coming back sooner.

    Problem with Hummingbird and Gravity forms:
    This is not on all pages I have the problem, but on some.
    One of them is https://dybdahlboligudlejning.dk/vil-du-udleje/

    You mentioned "a quick CSS fix".
    Do you need access to site?

    Thanks in advance.

    Kindest regards,
    Jorgen

    When I turn on Hummingbird , the form on: https://dybdahlboligudlejning.dk/vil-du-udleje/ will disapppear.

    You mentioned