Preview scrolling broke

Vince's Avatar


30 Mar, 2018 08:37 PM

MMD 4.3.2(76) on OSX 10.12.6.

I don't know when (this obviously worked at release, and for sometime after that), but preview scrolling broke. If you still have my big file, I open it, and position both editor and preview sections so the first line of the file is the first line of the screen. When scrolling in the editor window, the preview *immediately* (before one line has completely moved) jumps to about halfway through the document (the third sub-sub-topic underneath Third sub-topic). Scrolling from the top all the way to the bottom of the file (slowly, to eliminate sync problems) on the editing side only moves the Preview side about fifteen lines (to halfway through the fifth sub-sub-topic of the Third sub-topic).

Conversely, scrolling on the Preview side from where it is, the editor side scrolls all the way to the top when only scrolling the fifteen lines on the preview side. IOW, it's acting as if there are different-sized gears in the two sections. Moving the left (editor) side only moves the right side in very small increments (after immediately jumping to halfway through), and scrolling the right (preview) side moves the left side in huge increments (but only in a fifteen-line section of the preview side).

The preview options are both checked as always (Synchronize preview location when typing and Always synchronize scrolling). Note that I'm not typing — this is when scrolling with the touchpad/mouse.

I have a video if you can't duplicate it, but it's 145MB (it's only 20 seconds, and I shrunk the size of the window and trimmed it as much as I could), so you'll have to give me a Dropbox link again if you want it).

  1. Support Staff 1 Posted by Fletcher on 30 Mar, 2018 09:42 PM

    Fletcher's Avatar

    The file with lots of “lorem ipsum”?

    It seems to work fine for me — want to send me the exact file you have in case I made any changes to mine?

    One thing to try (if you haven’t already) is to toggle preview off and then on to reset the scroll map that is used to coordinate scrolling positions between the two views. Typing a character and then deleting it (don’t use space character for previously discussed reasons) will also reset the scroll map.


    Fletcher T. Penney
    Manager, Founder
    MultiMarkdown Software, LLC
    [email blocked]

  2. 2 Posted by Vince on 30 Mar, 2018 09:55 PM

    Vince's Avatar

    Yes. Here's the one I'm using.

    Turned it off and on, exited and re-entered MMD a half-dozen times or more, and just now did the latest Sierra security update and re-booted. No change.

    Let me know if you want the video.

  3. Support Staff 3 Posted by Fletcher on 30 Mar, 2018 11:11 PM

    Fletcher's Avatar

    It will probably be two days before I can take a look. Someone ran into me and took off so dealing with insurance and car repair, etc.


    Sent from my iPhone

  4. 4 Posted by Vince on 30 Mar, 2018 11:13 PM

    Vince's Avatar

    Uggh is right. No problem, praying everything will be taken care … well. :)

  5. Support Staff 5 Posted by Fletcher on 02 Apr, 2018 11:35 PM

    Fletcher's Avatar

    Are you using Sierra or High Sierra?

    In addition to typing, try toggling typewriter mode on and off (or off
    and on) and see if any of that resets things.

    I'll keep digging into it to see what I can find.


  6. 6 Posted by Vince Rice on 03 Apr, 2018 12:04 AM

    Vince Rice's Avatar

    Sierra. (Sorry, I usually try to remember to say.)

    No effect.

  7. 7 Posted by Vince Rice on 03 Apr, 2018 12:09 AM

    Vince Rice's Avatar

    It hasn't been until now, but it just showed itself to be sporadic. After I did the typewriter test, I closed MMD (I had opened it just for that test, it wasn't already open.)

    I then opened it again. It previewed OK.
    I closed it and re-opened it. It previewed OK.
    I closed it and re-opened it. It went back to the weird behavior.
    And has stayed there after three more tries.

  8. 8 Posted by Vince on 03 Apr, 2018 12:20 AM

    Vince's Avatar

    It appears to be related to the "initialization" of the preview side. By "initialization" I mean the text appearing in preview. Prior to initialization, it's just white with a rectangle at the top (I'm using GitHub CSS). Well, "top" relatively; since MMD doesn't do a very good job of syncing, the rectangle is at the bottom of the screen.

    When opening this document, it takes almost 2-3 seconds for the preview side to initialize. If I scroll (on the editor side, again with just the touchpad, nothing being entered) before the preview side has initialized, then the problem happens. If I wait until after the preview side initializes, it doesn't.

    No, "don't do that" is not an option. :) That 2-3 seconds is 2-3 seconds longer than any other MD editor I have.

  9. 9 Posted by Vince on 03 Apr, 2018 12:21 AM

    Vince's Avatar

    And I did say. :) My initial report said "… on 10.12.6".

  10. Support Staff 10 Posted by Fletcher on 03 Apr, 2018 12:51 AM

    Fletcher's Avatar

    That allowed me to recreate the issue. (At least once, anyways!)

    I'll try to see exactly where the program "flows" when you jump the gun
    with scrolling, and then see why updating the document doesn't fix it
    under those circumstances...


  11. 11 Posted by Vince Rice on 17 Apr, 2018 09:00 PM

    Vince Rice's Avatar

    Find anything on this?

  12. Support Staff 12 Posted by Fletcher on 18 Apr, 2018 11:31 PM

    Fletcher's Avatar

    Found one part so far -- should be able to improve the initial scroll position in next release.

    Still need to dig into the second part of the problem.


  13. Support Staff 13 Posted by Fletcher on 01 May, 2018 12:52 PM

    Fletcher's Avatar

    I posted a 4.4 beta release that should improve scrolling, as well as a few other things. Once it's been tested, it will be pushed out for general use:

  14. Fletcher closed this discussion on 01 May, 2018 12:52 PM.

  15. Fletcher re-opened this discussion on 05 May, 2018 07:08 PM

  16. Support Staff 14 Posted by Fletcher on 05 May, 2018 07:08 PM

    Fletcher's Avatar

    Updated beta (4.4 b4) with some additional scrolling tweaks, as well as a new Pro feature to open folders as single project windows.

    At bottom of this page:

  17. Fletcher closed this discussion on 05 May, 2018 07:08 PM.

Comments are currently closed for this discussion. You can start a new one.

Keyboard shortcuts


? Show this help
ESC Blurs the current field

Comment Form

r Focus the comment reply box
^ + ↩ Submit the comment

You can use Command ⌘ instead of Control ^ on Mac