Safezone makes canvas too big; hides page menu and carousel

[swissspidy]

Bug Description

Caused by #1310.
See #1244.
See #1245.

Expected Behaviour

Due to the safe zone that is being displayed above and below the page, the canvas pushes down the carousel, and makes it practically invisible on a "smaller" screen (tested on 15 inch MBP).

Steps to Reproduce

1. Open editor
2. Notice partially hidden page menu
3. Notice hidden carousel

Screenshots

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Acceptance Criteria

QA Instructions

[swissspidy]

cc @wassgha

[wassgha]

Hmm @dvoytenko did this happen before on 16:9?

[dvoytenko]

/to @wassgha let's address right away while it's fresh.

[dvoytenko]

Not that I know of, it did some measurements/calculations to ensure min-height.

[dvoytenko]

To correct my statement: there's a min-max calculation in the canvas/layout.js to avoid this issue specifically. My guess, simply, it needs to be adjusted for the new aspect ratio.