Fixed The space between some words disappear when double clicking and highlighting text with the mouse

Affected version
Description: the space between some words disappear when double clicking and highlighting text with the mouse.

Expected behavior: the space between the words shouldn't disappear

Steps to reproducte:
Highlight 3-4 words by double clicking on the first one then drag the mouse to the right to the 3rd or 4th word. Release the mouse button, then click on the highlighted text. Repeat, but this time after double clicking drag the mouse from right to the left. Click again on the highlighted text. Repeat a few times. It doesn't happen every time , but after a few tries (5-6), the space between some of the words disappear.
(Please also read the comments and watch the videos because the pattern of highlighting text seems to be different under Windows and Linux, to be able to reproduce the bug. For me at least.)

More info:

- can only be reproduced on Chrome (using Windows 10, eta: Under Linux too, but using a slightly different highlight pattern).
- can only be reproduced when user is logged in
- can only be reproduced when site Javascript is turned on
- can only be reproduced when highlighting non-quoted text
- can be reproduced in anonymous window with extensions turned off
- tested on 4 different xenforo 1 forums
- can not be reproduced on other non-xenforo sites (so not a Chrome bug, I guess)
- can not be reproduced on other xenforo 2 sites (well, at least not on

The affected sites which I tested are: , , and
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Chris D

XenForo developer
Staff member
This isn't something I can reproduce in my testing.

A video demonstrating the issue might be useful in case there's any steps we're missing.
Thanks for the quick reply Chris, sure I'll try to make a video and post it here. I spoke to another user of one of these forums and he managed to reproduce the bug too, so it's not just me.


Well-known member
I've noticed this in Chrome when using two XF 1 forums I'm a member of with paragraphs of text at random times. I didn't pay much attention to what I did but it involved highlighting text. I can't seem to get it to do it again right now for some reason :X3:
An important update: the bug doesn't happen when the selection includes the space after the last word
I'm confused now. I switched to Ubuntu 17.07 Chrome and after I only managed to reproduce the bug twice for 15 minutes of testing, I finally discovered something like a pattern. It seem that this time I had to first select a space between words rather than a word. Only then continue with selecting a word sequence. Then alternate between selecting space first or selecting word first, left to right and right to left ... I'm not quite sure, here's a video:
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