Please include here (Put code in between backticks
) exactly what you are attempting to add in the text widget.
Also, is this on a local install? If not, a link to your site may help.
And last, what browser/version are you using? Have you tried from another machine to see if the problem is with yours?
And you posted in this thread, so I will reply here:
You wrote:
This is a major issue since it involves default functionality in basic widgets using a default theme on multiple platforms.
If this was the case, we would be seeing this issue posted here very very many times. Since that is not occurring, then we need to correctly note that it’s not an issue affecting WordPress sites generally, but is affecting your site.