On Linux there is a separate “clipboard” that gets “clobbered” every time you highlight something. See my other comment on the matter or https://www.x.org/releases/X11R7.6/doc/xorg-docs/specs/ICCCM....

I know; I just pretend that clipboard doesn't exist. I've never found it convenient for anything other than pasting to terminals that screw up the CTRL-C/CTRL-V shortcuts.

Hmm. I am genuinely curious, how is it less convenient for you? To copy something to the clipboard you have to select it and press control–c, then to paste it you have to click where you want it to go and press control–v. That’s not very hard, certainly. But to use selection instead you only have to select it, then hover over where you want it and middle click. That’s fewer steps!

Of course I am assuming that your hand is already on the mouse. However, you said that you highlight things frequently as you read them, so I assume that’s what you meant.

because as I said, if I already have something on the clipboard, I don't want it to be overwritten by everything I highlight. a non-copying reason to highlight is the "search for" feature in a browser, I use that all the time. a very common thing is to highlight some text, then highlight some other text in an input field or text editing program, then paste to replace the highlighted text with the copied text. if all I had was the middleclick buffer, this wouldn't be possible.

Ah, I see. It looks like you have three similar reasons.

The first is something I guess I don’t do. If I select something that I want to paste somewhere, then I’m going to paste it right away; I already know exactly where it goes.

The second is that searching in applications you use frequently replaces the selection? That’s not how it’s supposed to work. Applications are supposed to claim the primary selection only when the user explicitly selects something, not merely when something is highlighted to make it more visible. Sad to hear that any application gets this one wrong; that’s supposed to be a pretty easy thing to get correct.

The third is about pasting into textboxes. This one is more subtle, but pasting from the primary selection into a textbox is supposed to replace the content of the text box, rather than appending to it. Certainly Firefox does for the urlbar, though to be honest I’m not sure that I’ve never noticed one way or the other if it does for anything else. Most of my text editing is done in Emacs, which doesn’t use textboxes very much, and which has a lot of other ways to quickly enter text without needing a lot of copy and paste.

Thanks for answering; it’s really interesting to see just how different people’s use–cases really are. I find selection to be more convenient because it’s simpler, while you find it to be less convenient because the programs you use aren’t as thoughtful, or because you use selection for other things. I guess we should both be glad that Linux implements both styles!

>The first is something I guess I don’t do. If I select something that I want to paste somewhere, then I’m going to paste it right away; I already know exactly where it goes.

I often want to paste things multiple times. e.g. I paste an interesting URL to an instant message chat, then maybe 10 minutes later I paste the same URL to someone else.

>The second is that searching in applications you use frequently replaces the selection?

no that's not what I mean. I'm talking about this: https://imgur.com/QiQiBLT.png

suppose I didn't know what "appending" meant and I wanted to search for it. I can highlight it, rightclick, then choose "search Google". I don't want to paste "appending" anywhere, I just want to search Google for it. but the act of highlighting it will overwrite whatever is in the middleclick buffer. so if that's the only clipboard I had, searching the web would interfere with copypaste, which is stupid.

>This one is more subtle, but pasting from the primary selection into a textbox is supposed to replace the content of the text box, rather than appending to it.

again that's not what I meant. I'm talking about taking a portion of the text in one textbox and replacing it with the text from elsewhere. for example, suppose I want to change part of the message I'm typing right now with lorem ipsum. it looks like this:

[1] https://imgur.com/GWldV00.png (ctrl-c copies)

[2] https://imgur.com/63RrISF.png (highlight destination. this overrides middleclick buffer, destroying the lorem ipsum copy if it were placed there)

[3] https://imgur.com/zGavx2b.png (ctrl-v pastes)

Sure, I understand. You can also do that by reversing the order of the two operations (paste into the document, then select and delete the unnecessary text), or you can use both selections (select the text to be copied while holding down alt, then select the text to replace while not holding alt, and middle click from the secondary selection by holding alt).

But that’s not really the point; the point is that it’s nice to have both mechanisms available. Some people will find selections more convenient, others won’t.