I considered necrobumping these two threads https://xenforo.com/community/threads/redactor-text-editor-lags-badly-when-using-opera.59832 https://xenforo.com/community/threads/redactor-responding-slowly-to-typed-text.81114/ but wanted to make it clear this is about XF v 1.4.5 Some members have reported seeing lag. I experience it as well, but only visibly on my cheaper, slower machine that I use when travelling; not on my more usual i5 box. So I set out to do some testing, using my lower spec laptop. Browser is Waterfox 35.0; OS is Windows 8.1u1 64bit. This is what I found: 1: I can detect lag when using AVForums. I can also detect lag when using this (XenForo) forum, but it is harder to detect (less severe). 2: I disabled each AVF add-on, tested for lag, and then re-enabled the add-on one at a time. No one add-on had a discernible effect. I did not disable multiple add-ons at any time. 3: The length of the thread in which the post is being attempted seems highly material. I could not detect lag when posting at AVF a reply to a thread with one other post. It was severe when posting a reply to a thread with over 60 other posts (a few pages long). 4: Different style templates at AVForums had no detectable effect; one style under development (the content/details of which I know nothing about) did appear perhaps to slow things further. 5: Switching to the BBCode editor removes the lag completely. 6: I monitored my task manager screen with one eye whilst watching my typing with the other! Total CPU was hovering around 4-6% with Waterfox hovering around 2%. As soon as I start typing, Waterfox hits around 17% until the text is placed in the input field, and then drops again. At this point, I'm not really sure whether I am reporting a bug or asking for help to resolve an issue. Either way, some users are claiming the site to be unattractive to use, and I can see why. Grateful for any insight or help. ============================ Description of the issue and some personal guessed attempts at conclusions (the latter more to assist with the description than anything else): Description In a post reply input field, type fairly quickly. Nothing appears on the screen until you pause typing, and then after 1/2 second or so - a brief but noticeable pause - your keystrokes appear, often in one action, but sometimes in more than one distinct action. Possibilities It's as if the keyboard buffer is only EITHER accumulating OR depositing (and never both). And it waits for a gap in the input before it outputs. It's the length of that gap that appears to vary - which means you end up with more or less buffered keystrokes before they appear. If the gap is very short, then each keystroke will appear almost right away; so the problem is not detectable. If the gap is long, one can easily type 20 characters before anything appears on screen. The length of the gap (and hence the severity of the issue) seems to be affected primarily by the speed of the machine and/or other concurrent demands being placed on it - whether by the website itself or (presumably) other applications. - My i5 machine never visibly exhibits this (CPU benchmark score 3121; Win7). My much slower AMD1450 machine exhibits this (CPU benchmark score 1624; Win8.1u1). Conclusion: Machine speed is material - It's consistently very noticeable at AVForums and much less so at XenForo. Conclusion: AVF is likely to be more script-heavy due to design and add-ons than XF. Suggests that demand on the machine/browser is material. - The length of the thread has an effect. Suggests there is something about page content and/or user details panels that is adding to demand on the machine. Perhaps something like the on-line indication for each poster as an example/illustration. - The BBCode editor cannot be made to exhibit this symptom. Conclusion: This is an artefact of Redactor specifically.