Sizer VS WindowGrid

Here's a solution if you don't want to manually resize. I use a windows utility (Sizer) http://brianapps.net/sizer/ to size the window on the other monitor to fit the screen, That way it looks maximized but doesn't prevent me from switching to other windows. I've bound the Sizer app to a keyboard shortcut. That way I can detach the mixer, move it to the 2nd monitor, then use Sizer to max. Source: about 2 years ago

On my Windows PC I am using Window Grid , which is my favorite way to manage windows, and would love a macOS equivalent. If you haven't used it, basically it adds a right click function only when you grab a window to move it - so grabbing a window with left click (holding it down), right-clicking and then a grid pops up to help you resize and realign that particular window. Here's a gif from their website. This... Source: about 1 year ago

Free: Search Everything (helps find files and stuff https://www.voidtools.com/ ) WizTree (you can see file sizes visually and helps you find stuff that take too much space.https://www.diskanalyzer.com/ ) EarThumpet (better volume mixer than the windows one https://apps.microsoft.com/store/detail/eartrumpet/9NBLGGH516XP?hl=en-us&gl=US ) ShareX (screenshot ktl. https://getsharex.com/ ) Displayfusion (gia dual... Source: almost 2 years ago

Another approach that does not involve the Alt key is WindowGrid and of course there is Microsoft's own FancyZones PowerToy. Source: about 2 years ago

I currently run 6 alts at the same time, to organize the windows I use a program that lets you easily place the clients in a neat grid of your choice http://windowgrid.net/. Source: over 2 years ago

You'll probably like WindowGrid. It's like fancy zones on steroids while also being simpler to use. Source: over 2 years ago