How can I stop my retina display from taking 2x sized screenshots? I recently got a retina display MacBook, and all my screenshots (via ⌘ CMD+⇧ SHIFT+3 or ⌘ CMD+⇧ SHIFT+4) end up being twice the size compared to how they appear on-screen.
For example, here is a screenshot of the Ask Different logo taken via ⌘⇧4 on a retina MacBook Pro running macOS 10.15.7:

When the file is opened locally in Preview or Quick Look, it appears at the same size as the website's logo. But when uploaded to the web, it displays twice as big.
How can I stop this from happening?
Here is the most convenient solution
(Taken from http://www.quora.com/How-can-I-get-my-retina-Mac-to-not-take-screenshots-that-are-too-big and modified a bit)

Use OsX embedded Automator to downsize screenshots automatically after they taken.


Open /Applications/Automator
Create a "Folder Action"
At the top of the window, where it says "Folder Action receives file and folders added to", select "Desktop"
From the panel on the left, select "Files &amp; Folders" and drag the item "Filter Finder Items" to the right panel.
Add the following conditions to the Filter Finder Items action: Name begins with "Screen Shot"; Kind is image.
(Optional step: if you want to keep copy of originals) - From the Actions list on the left, find "Copy Finder Items" and drag it to the panel on the right. Set the destination folder for the image copy (for example: "To: Pictures")
In the Actions library on the left, click on "Photos" and drag the "Scale Images" action to the right panel.
In the Scale Images action, select "By Percentage" from the drop-down and set the value to 50.
Select File > Save and give the Folder Action a snappy name like "Smaller Screenshot Copy"




Here is saved workflow file