When copying text from web pages in Firefox on my Mac, the pasted text in Legend has double spaces between some words. For example, if I copy some text from Legend’s home page, the HTML on the clipboard, as shown in Clipboard Viewer, looks like this:
<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body><div class="pt-8 pmb-2"><p>Being organized should be easy.</p><p>But it's hard when everything is spread between multiple incompatible apps that don't handle your particular challenges.</p><p>Legend
brings all of your productivity into one place and accommodates your
organizational style, so you can just get things done.</p></div></body></html>
Note that in the third paragraph, there are hard line breaks after “Legend” and after “your”. The line breaks aren’t in the page’s source HTML, they seem to be artifacts of copying from the displayed page in Firefox, even though there aren’t line breaks at those places on the screen. They should be ignored (multiple spaces and line breaks in HTML should be reduced to a single space) but Legend converts them to spaces, creating double spaces after those words:
Fyi, the clipboard also contains a plain-text version, which doesn’t have extra spaces in it. Safari and Vivaldi (Chrome fork) don’t have extra line breaks in their HTML.