Remove unused preview plugin

[juliusknorr]

The files app does no longer support javascript based preview plugins since Nextcloud 18

[juliusknorr]

/backport to stable18

[juliusknorr]

/compile /js

[cypress]

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Test summary

11 • 1 • 0 • 0

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Run details

Project	text
Status	Failed
Commit	6ad8424
Started	Apr 20, 2020 10:26 AM
Ended	Apr 20, 2020 10:28 AM
Duration	01:34 💡
OS	Linux Ubuntu Linux - 18.04
Browser	Electron 78

View run in Cypress Dashboard ➡️

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Failures

	cypress/integration/viewer.spec.js ⏯		1
1	Open test.md in viewer > Open the viewer on file click

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[skjnldsv]

Icon changed
CypressError: Timed out retrying: Expected to find element: '#viewer-content .modal-header button.icon-menu-sidebar-white-forced', but never found it.

button.icon-info-white-forced

I wondered if we should create some dedicated functions in a library so it's easier to use? I feel like just using css rules that are duplicate seems a bit weird 🤔

[juliusknorr]

Yep, that is fixed in a separate PR.

I think we could even drop that test as for text it should be fine to assume that the viewer does its stuff properly, however I added a case for it back then since we were the only app integrating at that point in time.

[backportbot-nextcloud]

The backport to stable18 failed. Please do this backport manually.

[juliusknorr]

/backport 35b2f07 to stable18

[backportbot-nextcloud]

backport to stable18 in #783 with conflicts ⚠️

[juliusknorr]

/backport 69e0eca to stable18

[backportbot-nextcloud]

The backport to stable18 failed. Please do this backport manually.

[juliusknorr]

/backport 69e0eca to stable18

[backportbot-nextcloud]

backport to stable18 in #784 with conflicts ⚠️