Problem with start Qt application

Hi guys
I’ve installed telegram and webots from snap store
but after i run them i encountered these 2 errors

for Telegram :

Invalid MIT-MAGIC-COOKIE-1 keyqt.qpa.xcb: could not connect to display :0
qt.qpa.plugin: Could not load the Qt platform plugin “xcb” in “” even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the appli
cation may fix this problem.

Available platform plugins are: eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, wayland-egl, wayland,
wayland-xcomposite-egl, wayland-xcomposite-glx, xcb.

Aborted (core dumped)

For Webots :

Invalid MIT-MAGIC-COOKIE-1 keyWarning: could not connect to display :0
Info: Could not load the Qt platform plugin “xcb” in “/snap/webots/20/usr/share/webots/lib/webots/qt/plugin
s” even though it was found.
Fatal: This application failed to start because no Qt platform plugin could be initialized. Reinstalling th
e application may fix this problem.

Available platform plugins are: xcb.

/snap/webots/20/usr/share/webots/webots: line 90: 3776 Aborted (core dumped) “$webots_home
/bin/webots-bin” “$@”

how can i fix it ?

Hello and welcome to the openSUSE forums.

Please be aware that programs from snap store are not openSUSE supported or tested programs. Thus helping depends on general knowledge and onpeople that happen to use the same program as you do.

You did not tell us how you start the programs. To me it looks as if you start them outside of a desktop session (I am not sure about that though), because of the problems connecting to display :0.

And then something we want to tell all new members here:
There is an important, but not easy to find feature on the forums.

Please in the future use CODE tags around copied/pasted computer text in a post. It is the # button in the tool bar of the post editor. When applicable copy/paste complete, that is including the prompt, the command, the output and the next prompt.

An example is here: Using CODE tags Around your paste.

Hi unloadble,

For Telegram snap store is not necessary. It’s in the main repository:

**~ #** zypper se -s telegram 
Metadaten von Repository 'Signal' abrufen .........................................................................................................................................................[fertig] 
Cache für Repository 'Signal' erzeugen ............................................................................................................................................................[fertig] 
Repository-Daten werden geladen... 
Installierte Pakete werden gelesen... 

S  | Name                           | Type  | Version              | Arch   | Repository 
---+--------------------------------+-------+----------------------+--------+----------------------- 
i  | libpurple-plugin-telegram      | Paket | 1.4.2-bp153.1.22     | x86_64 | Haupt-Repository (OSS) 
i  | libpurple-plugin-telegram-lang | Paket | 1.4.2-bp153.1.22     | noarch | Haupt-Repository (OSS) 
i+ | pidgin-plugin-telegram         | Paket | 1.4.2-bp153.1.22     | noarch | Haupt-Repository (OSS) 
i+ | telegram-desktop               | Paket | 2.5.8-bp153.1.14     | x86_64 | Haupt-Repository (OSS) 
   | telegram-theme-adapta          | Paket | 3.95.0.11-lp153.1.42 | x86_64 | Haupt-Repository (OSS) 
   | telegram-theme-plata           | Paket | 0.9.9-lp153.1.86     | noarch | Haupt-Repository (OSS)



You can install it with YaST or

zypper in telegram-desktop