Scrolling upwards jumps to top post


(Felix Freiberger) #1

I found a quirk with infinite scrolling:

When I open this topic here, scroll down to the bottom and then scroll up slowly, the view jumps into the first post:

Version information Meta is currently running `Discourse 1.6.0.beta7 - https://github.com/discourse/discourse version 9e75b14535b401346ac6547d883d9b3901407eec`, I am running Chrome `Version 51.0.2704.84 m (64-bit)`.

(Sam Saffron) #2

Does this also happen for you in incognito?


(Felix Freiberger) #3

I put on my :spy: glasses, but it’s still jumping.


(Sam Saffron) #4

OK I have a repro @eviltrout happens when:

$(window).width()
1024
$(window).height()
657

Confirmed in incognito.

Does not happen when height is 957 FWIW


(Robin Ward) #5

Very tricky bug to track down, but it seems related to uncloaking. This should fix it:


(Robin Ward) #6

(Alan Tan) #7

@eviltrout I just got this on

$(window).height()
1291

Steps to repro

  1. Use sidebar and jump to last post.
  2. Start scrolling up

(Alan Tan) #8

(Robin Ward) #9

I’ve tried several times and I can’t reproduce this.

Can you list your Chrome version and OS?

Also just to confirm, it’s still happening for you right now on meta?


(Alan Tan) #10
Google Chrome	51.0.2704.63 (Official Build) (64-bit)
Revision	2989ec7055a268f05554172b2207a34c0c842b8d-refs/branch-heads/2704@{#656}
OS	Linux 
Blink	537.36 (@2989ec7055a268f05554172b2207a34c0c842b8d)
JavaScript	V8 5.1.281.47
Flash	21.0.0.242

Yup just tested on my laptop and I’m getting it as well. Mine doesn’t jump to the top post but it jumps from post 40 to about 20+


(Robin Ward) #11

Did your laptop have the same height too? Or were you able to reproduce it on a different height.

Has anyone else managed to reproduce this? I feel so powerless between this and @zogstrip’s keyboard bug that I can’t seem to reproduce no matter what I do.


(Jeff Atwood) #12

I definitely cannot repro in Chrome / Windows. My $(window).height() is only around 900 though.


(Sam) #13

I am able to repro on the new right gutter topic as well, fairly consistently but not every time.

Repro:

  1. Load the topic fresh at the very bottom
  2. Begin scrolling up at a nice clip
  3. Note posts uncloaking at post ~62/63
  4. Jump to post ~42/43
  5. Keep scrolling while this is happening
  6. Jump to post ~22/23

Env:
Chrome Version 51.0.2704.84 m, Windows 10
Window height: 955
Window width: 1920

I can also get this to happen with a browser height of 407 (width 950) at about the same points (low 60s, low 40s, and sometimes low 20s in the post count). Always jumps about 20 posts. Not sure if browser height actually related to bug.

Step 1, I should note, is very important to reproducing this, so let me clarify my probably imprecise repro step:

  1. Go into the topic
  2. Scroll to the very bottom so that your last read position is there
  3. Refresh the page

This seems to be necessary to consistently reproduce the bug. I can’t say it never happens if you just go from say /latest to the topic and scroll up, but yeah. Once it’s happened in a topic, a refresh seems to be necessary to get it to happen again.


(Sam Saffron) #14

I remember @eviltrout fixing something in this department recently.

Is it still an issue?


(Felix Freiberger) #15

I think it’s fixed – I’ll flag to re-open if it happens again.
Thanks, @sam and @eviltrout! :slight_smile:


(Sam Saffron) #16