[Bug]: App Crashs after a while

[PurpleSmurf2]

Preflight Checklist

• I have searched the issue tracker for a bug report that matches the one I want to file, without success.

OpenComic Version

1.6.5

Operating System

Linux Mint 22.3 Cinnamon based on Ubuntu 24.04.3

Installed via

flatpak

Steps to reproduce

1. Open app with console flatpak run app.opencomic.OpenComic
2. Get flooded with error messages while looking through comics, manga..
3. Wait for crash

Expected Behavior

It does not crash.

Actual Behavior

It crashes.

Error message

 08:11:33.550: Failed to load module "xapp-gtk3-module"
[3:0201/081133.587627:ERROR:dbus/bus.cc:408] Failed to connect to the bus: Failed to connect to socket /run/dbus/system_bus_socket: Datei oder Verzeichnis nicht gefunden
[3:0201/081133.587660:ERROR:dbus/bus.cc:408] Failed to connect to the bus: Failed to connect to socket /run/dbus/system_bus_socket: Datei oder Verzeichnis nicht gefunden
LaunchProcess: failed to execvp:
xdg-settings
Warning: win.show() from did-finish-load and not from ready-to-show

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.344: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:61): GLib-GObject-CRITICAL **: 08:11:42.345: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:184:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:186:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:184:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:186:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:184:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:186:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:184:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:186:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:184:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:186:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:184:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:186:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:184:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:186:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:184:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:186:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:184:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:186:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s._sendInternal (node:electron/js2c/browser_init:2:94481)
    at b._sendInternal (node:electron/js2c/browser_init:2:78782)
    at node:electron/js2c/browser_init:2:110311
    at new Promise (<anonymous>)
    at Object.invokeInWebContents (node:electron/js2c/browser_init:2:110040)
    at b.executeJavaScript (node:electron/js2c/browser_init:2:81193)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:184:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:186:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:184:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)
Error sending from webFrameMain:  Error: Render frame was disposed before WebFrameMain could be accessed
    at s.send (node:electron/js2c/browser_init:2:94265)
    at b.send (node:electron/js2c/browser_init:2:78703)
    at Timeout._onTimeout (/app/main/resources/app.asar/scripts/main.js:186:20)
    at listOnTimeout (node:internal/timers:588:17)
    at process.processTimers (node:internal/timers:523:7)

Additional Information

The error report has been shortened. It contains hundreds of thousands of similar errors.

Sample file

No response

[ollm]

Thanks for reporting!

It may be related to #511.

The GLib errors are caused by sharp, which is used for thumbnail generation and image interpolation. You can try disabling image interpolation via sharp in the app settings to see if the problem persists (Set both options to Disabled (Chromium)).

[PurpleSmurf2]

I disabled both options as suggested and restarted the app. Unfortunately, it didn't help. The same errors occur, even causing the app to crash.

Edit:
It is also not a specific file that causes the app to crash. If the app crashes on a certain file and I then reopen it, it works and then crashes on another file. This usually happens when I load a file, click back, and load another file. Sometimes it happens after the first time, but sometimes only after the tenth time.

edit2:
But yes, the error report you linked to basically works like this. Some .cbz or .cbr files can be relatively large, up to a gigabyte. It could be that the memory is filling up somewhere. Image file formats in the tested .cbz files were .jpg, .png, and .webp.
However, it has not been possible to have a longer session so far.

[ollm]

Based on what you describe, it's possible that the crash is related to file extraction using 7zip.

Currently, OpenComic supports extracting multiple files at the same time to better take advantage of the available CPU cores. For large files, it can also split the extraction into multiple processes. It's possible that loading several files simultaneously is causing this issue.

I've made two builds from the master branch, one with the current behavior, and another with extraction limited to one file at a time. You can try both, maybe the error is in some dependency and has already been fixed in the master branch, since it's more up to date.

Build with the current behavior:
https://mega.nz/file/PLQGWa4A#SVrL7mgaRiplNd04r3dsfrwKb0dQwIUurJUzzuimRok

Build with extraction/file reading limited to one at a time:
https://mega.nz/file/6DRzXZ5L#OSlYnNtx-aw3YrUpNAhURRN_uRoX2o1I-FG_k6taBdg

[PurpleSmurf2]

I tested both builds and both crashed with the same error messages as before. However, I did some more research on the cbz files used and their content. Apparently, high resolutions often lead to the aforementioned crash. For example, a cbz file with a resolution of 1500 x 2250 and 200 images ~ 40MB file size can be loaded quickly and easily, and there are no problems opening similar files afterwards with the same resolution and number of pages.

Another file, however, with a resolution of 6000 x 7000 and 100 images ~100MB each file also loads correctly, but if you then try to open a similar file, the app crashes.

Restarting the app and attempting to open a file with 400 images, each with a resolution of 6000 x 7000 ~ 1.2GB file size, immediately causes the app to crash.

Gtk-Message: 18:03:08.936: Failed to load module "xapp-gtk3-module"
[3:0202/180308.972696:ERROR:dbus/bus.cc:406] Failed to connect to the bus: Failed to connect to socket /run/dbus/system_bus_socket: Datei oder Verzeichnis nicht gefunden
[3:0202/180308.972736:ERROR:dbus/bus.cc:406] Failed to connect to the bus: Failed to connect to socket /run/dbus/system_bus_socket: Datei oder Verzeichnis nicht gefunden
LaunchProcess: failed to execvp:
xdg-settings
Warning: win.show() from did-finish-load and not from ready-to-show
[3:0202/180312.149947:ERROR:ui/gfx/x/atom_cache.cc:232] Add _NET_WM_STATE_MODAL to kAtomsToCache

(process:63): GLib-GObject-CRITICAL **: 18:03:15.972: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:63): GLib-GObject-CRITICAL **: 18:03:15.972: g_object_ref: assertion 'G_IS_OBJECT (object)' failed

(process:63): GLib-GObject-CRITICAL **: 18:03:15.972: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

(process:63): GLib-GObject-CRITICAL **: 18:03:15.972: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

Edit: I asked chatgpt for a small script. You can use it to test the resolutions so that there are no copyright infringements here. Simply create the images yourself with imagemagick in the desired quantity and resolution, and then pack the images into a cbz file, for example with the command “zip mycomic.cbz *.webp”.

#!/usr/bin/env bash

if ! command -v convert >/dev/null 2>&1; then
  echo "Error: ImageMagick (convert) is not installed."
  echo "On Debian/Ubuntu for example: sudo apt install imagemagick"
  exit 1
fi

read -rp "How many images should be created? " COUNT
if ! [[ "$COUNT" =~ ^[0-9]+$ ]] || [ "$COUNT" -le 0 ]; then
  echo "Please enter a positive number."
  exit 1
fi

echo "In which format should the images be created?"
echo "Examples: png, jpg, jpeg, webp, gif ..."
read -rp "Format: " FORMAT

read -rp "Image width (e.g. 800): " WIDTH
read -rp "Image height (e.g. 600): " HEIGHT

if ! [[ "$WIDTH" =~ ^[0-9]+$ ]] || ! [[ "$HEIGHT" =~ ^[0-9]+$ ]]; then
  echo "Width and height must be integers."
  exit 1
fi

OUTDIR="output_images"
mkdir -p "$OUTDIR"

echo "Creating $COUNT images in .$FORMAT with resolution ${WIDTH}x${HEIGHT} in folder '$OUTDIR' ..."

for ((i=1; i<=COUNT; i++)); do
  # Generate random colors (hex)
  R1=$(printf "%02x" $((RANDOM % 256)))
  G1=$(printf "%02x" $((RANDOM % 256)))
  B1=$(printf "%02x" $((RANDOM % 256)))
  R2=$(printf "%02x" $((RANDOM % 256)))
  G2=$(printf "%02x" $((RANDOM % 256)))
  B2=$(printf "%02x" $((RANDOM % 256)))

  COLOR1="#$R1$G1$B1"
  COLOR2="#$R2$G2$B2"

  FILE="$OUTDIR/image_$i.$FORMAT"

  convert -size "${WIDTH}x${HEIGHT}" \
          "plasma:$COLOR1-$COLOR2" \
          -colorspace sRGB \
          "$FILE"

  echo "Created image $i: $FILE"
done

echo "Done."

Edit3:

I created 3 testfiles. 200 Images Resolution 3000 x 4000. Switching between them crashes the app. Here is the Link to test the files.
Download Testfiles