pkcon update
Getting updates [=========================]
Finished [=========================]
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Finished [ ] (0%)
The following packages have to be updated:
neon-settings-0.0+p18.04+git20190214.1047.all Settings and artwork for KDE neon
Proceed with changes? [N/y] y

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Updating packages [=========================]
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Running [=========================]
Installing packages [=========================]
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Fatal error: Error while installing package: new neon-settings package pre-installation script subprocess returned error exit status 2

Solved, Firefox-esr and Firefox conflict, deleted Firefox-esr