Description:
An object with an animation effect disappears a few steps ago. Even if "Go one step" is executed, it is not restored, and if "Step back" is repeated several times, it is restored to some extent. The emphasis effect such as "spin" disappears or becomes thin after the effect ends. When you use the screen enlargement function in Linux and execute "Forward" in the enlarged state, "Forward" progresses abnormally or the page jumps.

Steps to Reproduce:
1.Prepare multiple objects.
2.Give the object an animation effect.
3.For the effect, select something other than "appear" and give a motion path.
4.Depending on the version, it may be improved by hardware acceleration, but turning this feature on or off does not matter.
5."Go one step" will cause one object to appear as an effect.
6.Occasionally, try "Go Back One".


Actual Results:
While the animation effect is running, the objects around it disappear as if blinking, and are restored after the effect ends. Not seen in older versions such as 6.1. Previously, turning hardware acceleration on could help, but the current stable version doesn't care.
If you press "Return" while playing the presentation even once, the animation effect does not proceed even if you return from there. In addition, it goes on in steps.
If you execute "Forward" while expanding the screen with linuxmint, the order of pages and effects on the screen will be greatly changed.

Expected Results:
Video swap problem?
It's not a memory allocation issue for settings.
A similar situation repeats as the version changes.


Reproducible: Always


User Profile Reset: No



Additional Info:
impress animation strange behavior
Animation behavior Strange behavior 
① Behavior on returning

② Behavior on spin

③ Bug while expanding screen screen

① Apply animation effects to multiple objects "Appear" works normally. Return the anime effect with "Return". Then, with the "fade etc" effect, the previous objects that were moved a few times disappear. This is seen in version 6.2 and above. In the final version of version 6.1, you can play back normally. 

② The object disappears when you spin it with the spin animation. To be precise, the arc line that is spun becomes so thin that you cannot see it. it.

③ It is assumed that the presentation is being executed by expanding the screen of the accessibility function with Linux Mint. At this time, if the magnification is greater than 1 and the presentation is set to “advance” in that state, the progress is greatly advanced or the next slide is skipped. This is not seen in version 6.1.