Copy and paste links and addresses with several lines(Firefox, Thunderbird)

               You sometimes get long links via email that are mutilated due to the line breaks. You always need to put them together and want to know how this can be done faster and better hereafter.
               Contrary to what some people believe, the browser in the address bar accepts a URL with several lines with line breaks as an entry without any problem. Ditto for a few other browsers.

               The only difference lies in making entries in text fields such as in Google Mail. In case of fields with several lines like in the field for message texts, the copied texts are always entered with the contained line breaks. In text fields with a single line such as the subject, the behavior depends on a hidden setting. In order to adjust this setting, enter “about:config” in the address line and press Enter. Confirm the warning by clicking “I will be careful”. In the “Filter” field, enter “editor.singleLine. pasteNewlines”.
                For further editing, double click the entry in the list. The value “0” adopts everything without any changes whereas the value “1” accepts the content only up to the end of the first line. This was the same in Firefox 2 and is also applicable for Internet Explorer. From Firefox 3, the value is set to "2" by default and it leads to line breaks being replaced with blanks. It is also more practical to remove the line breaks completely or to replace them with command, which you can do with values “3” or “4”. Then confirm the change with “OK” and restart the browser.
                Thunderbird also has this configuration. It is effective for instance when you copy an address in the “To” field when composing a new message. In order to ensure that the addresses are correctly used, they must be separated using a comma. The value “4” is thus most practical for the configuration setting.