The problem is not that you need to find one of the options that is clickable. All the links are all non-clickable because the cookie dialog is covering them.
This is how you can dismiss the cookie dialog and the gray mask which covers the main page
cy.visit('https://www.qi-digital.de');
// in case the cookie is already set and the mask does not appear
// use a conditional check first
cy.get('body').then($body => {
if ($body.find('#SgCookieOptin').length) {
cy.get('.sg-cookie-optin-box-close-button').click()
}
})
// now just click the link
cy.contains('a', 'Impressum').click()
// and confirm the new page appears
cy.contains('h1', 'Impressum', {timeout:10_000}).should('be.visible')
It seems to me that in the test runner, the cookie dialog always appears, in which case you can simplify the test
cy.visit('https://www.qi-digital.de');
// remove the cookie dialog
cy.get('.sg-cookie-optin-box-close-button').click()
// now just click the link
cy.contains('a', 'Impressum').click()
// and confirm the new page appears
cy.contains('h1', 'Impressum', {timeout:10_000}).should('be.visible')
Clicking the "Impressum" link on the cookie modal
This code will click the "Impressum" link that is on the footer of the cookie modal.
I added some code to clear application data to force the modal, but it's not consistently showing the cookie modal.
cy.clearCookies()
cy.clearLocalStorage()
cy.get('#SgCookieOptin') // cookie modal
.find('a:contains(Impressum)') // find the link in the modal footer
.then($a => $a.removeAttr('target')) // stop new browser tab opening
.click()