Copy should copy as is. Where are you copy from and to?

There is a pref added to make it possible to paste spaces instead of percentage encoding.

You can look at this pref on the about:config page to enable/disable this feature.

• browser.urlbar.decodeURLsOnCopy

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.

• http://kb.mozillazine.org/about:config

I am copying from the Address Bar, which I guess is called URL Bar in the configs. The URL shows up there with a space and copy/paste is keeping it as a space.

browser.urlbar.decodeURLsOnCopy is set to false, the default value.

When Firefox decodes the %20 to spaces when you paste in the location bar then there is no way to get these characters re-encoded once again.

I'm not pasting into the "location bar". I browse to a certain URL. Then I want to copy that URL and paste in a different tool.

This is not a user error. I've been doing this for > decade. The behavior of FF changed with the 53 release.

Copy the address. Then paste it to a word type program. Is the problem still there?

> Copy the address. Then paste it to a word type program. Is the problem still there?

Yes, #$@# it! I am not a beginner.

Can you confirm that you see %20 in the location bar?

"Can you confirm that you see %20 in the location bar?"

No it is not %20, but literal spaces in the "location" bar. This is exactly what I said in my question: "Since the upgrade to 53.0.3, URLs with encoded spaces now appear in the address bar with literal spaces."

For those who have not read the question, I repeat it here:

"FF Version 53.0.3, OS X Sierra 10.12.5.

Since the upgrade to 53.0.3, URLs with encoded spaces now appear in the address bar with literal spaces. When copied via clipboard and pasted elsewhere, those remain as literal spaces. Creates quite a problem. "