Web: Image previews change size causing scroll pop

Description

This happened on community-release and mysql.test on Firefox and Desktop on Mac

The placeholder for a loading image uses the actual size of the image, but the actual image has a max width added as part of the fix for MM-14486. The following are two screenshots of the app, before and after the image linked below is loaded:

Note that the thumbnail is larger than the loaded image

Repro steps:
1) Post the following link

Observed: The placeholder for loading the image is larger than the image itself, causing the page layout to change when the image is loaded
Expected: The placeholder is the same size as the final image

QA Test Steps

See description

Status

Mana

None

Assignee

Sudheer Timmaraju

QA Assignee

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Reporter

Harrison Healey

Epic Link

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Fix versions

Mattermost Team

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