http://www.quickandeasywebbuilder.com

I cannot find anything wrong in your project.
What are the exact steps to reproduce the problem?

I do not think the behavior Mega menu is affected by the version of the macOS.
To be able to help you, I need a demo project so I can see all your settings.

It looks like you have added empty or incomplete items to the 'hreflang' section of the Page Properties.

QWB has built-in form validation.
http://www.quickandeasywebbuilder.com/validation.html

But you can also add custom code via the HTML object or Page HTML
http://www.quickandeasywebbuilder.com/add_html.html

There is currently no way to exclude pages from the search index, but I will investigate if this can be added in a future update.

Did you use correct filenames for the adaptive images?
Filenames should include pixel density descriptors such as 1x, 1.5x, 2x, and 3x.

Example:
filename@1.5x.png
filename@2.0x.png

The mega menu has not been changed recently. Maybe you have used conflicting settings? For example, maybe you have added an 'onclick' event to the page which disables default click behavior? Or maybe you have added a link to the main button, so the click triggers a link instead of opening the submen...

The problem should be fixed in the latest update:
viewtopic.php?f=1&t=46041

The zip is 32bit otherwise it would have '64' in the filename. The files in the zip are exactly the same as in the Debian package. The only difference is that they will be copied automatically to the application folder. The Debian package for version 6 (64bit) can be downloaded here: https://www.qui...

What's new in 7.1.2? - Fixed: Cloning a page with flexgrid does not include breakpoint data. - Fixed: Server sided form validation does not throw exception. - Improved: Added quotes to font-family when using 'Automatically use @font-face' - Improved: Menubar script is now compatible with 'Move javac...

Thanks for the demo project.
I was able to reproduce the problem based on the provided information and it will be fixed in the next update.

First note that version 2 is very old and no longer supported. However, Vimeo has not changed over the last few years, so it should work. Note that the player functionality is directly loaded from the Vimeo website so the only thing that can be wrong is the video ID. Or maybe your browser's security...

Preloading screen with CSS animations. Based on a script by Petr Tichy. https://ihatetomatoes.net/create-custom-preloading-screen/ http://www.quickandeasywebbuilder.com/extensions/pictures/preloadingscreen.jpg You can download the new extension through the Extension Manager (Menu->Tools->Extension M...

I'm sorry, flex grids currently do not support forms.
But you can have a layout grids and flexgrids on the same page (not nested).

All the mentioned menus should work.
To be able to help you, I need a demo projetc so I can see all your settings.