Slidin and slidout together doesn't work

[DIYEmbedded]

Expected Behavior

Image should slidin and slideout

Actual Behavior

either slidin or slideout work, both doesn't work together

Specifications

• Python Version: 3.11.10
• MoviePy Version:2.1.2
• Platform Name: Windows 11
• Platform Version: 24H2

[DIYEmbedded]

code is

from moviepy import VideoFileClip, TextClip, ImageClip, CompositeVideoClip, vfx

img_clip = ImageClip("img4.jpg", duration=(5.0))
img_clip = img_clip.with_start(0)
img_clip = img_clip.resized([1280,720])

[alvarofranz]

I confirm the bug, when applying the SlideIn and SlideOut effect to the same clip, only one works.

Doing:

effects_list.append(vfx.SlideIn(SLIDE_DUR, "left"))
effects_list.append(vfx.SlideOut(SLIDE_DUR, "right"))
clip = (ImageClip(img_file)
                .with_duration(total_scene_duration)
                .with_effects(effects_list)
                .with_start(start_t))

Python Version: 3.13.2
MoviePy Version: 2.1.2
OS: MacOs Sequoia 15.3