Impacted versions: 11.0

Steps to reproduce: Uninstall Signup module --> Go to General Settings --> Make a Change in Some Configuration --> Save

![](https://image.prntscr.com/image/ehf0ZrHGRrG45SO0jZIUVg.png)

Current behavior: Traceback on Screen

![](https://image.prntscr.com/image/XHFHi-z8TJePn2X_0jvZWg.png)

Expected behavior: Should be able to Save Settings

Video/Screenshot link (optional):


addons/website/models/ir_model_fields.py
from odoo import api, models
class IrModelFields(models.Model):
    _inherit = 'ir.model.fields'
    @api.multi
    def unlink(self):
        
        
        social = (
            'social_facebook',
            'social_github',
            'social_googleplus',
            'social_linkedin',
            'social_twitter',
            'social_youtube',
        )
        self = self.filtered(
            lambda rec: not (
                rec.model == 'res.company' and
                rec.name in social
            )
        )
        return super(IrModelFields, self).unlink()