Sidebar does not appear if the "Open sidebar" button was clicked while the image was loading

[knuxify]

Describe the bug When an image is loading, clicking the "Open sidebar" button will cause the button to disappear and the sidebar to not appear. Sometimes the space for the sidebar is not reserved at all, and sometimes the sidebar leaves leftover space.

To Reproduce Steps to reproduce the behavior:

1. Click on a photo
2. While it's loading, click the "Open sidebar" button at the top of the photo viewer

Expected behavior The sidebar appears, either before the photo loads (with placeholder data) or after the photo loads.

Screenshots

Browser logs:

Opening viewer for file  (filename censored) viewer-main.js:374:3626
A files list have been provided. No folder content will be fetched. viewer-main.js:374:5798

(Also, earlier on, while loading the gallery I also get these, but this might be unrelated:)

The following mime is already registered image/svg+xml 
Object { id: Getter & Setter, group: Getter & Setter, mimes: Getter & Setter, component: Getter & Setter, … }
viewer-main.js:374:7723
The following mime is already registered text/plain 
Object { id: Getter & Setter, mimes: Getter & Setter, component: Getter & Setter, group: Getter & Setter, … }
viewer-main.js:374:7723
The following mime is already registered text/csv 
Object { id: Getter & Setter, mimes: Getter & Setter, component: Getter & Setter, group: Getter & Setter, … }
viewer-main.js:374:7723

System info:

• OS: Arch Linux
• Browser: Firefox 81.0.1
• Nextcloud version: 19.0.4

[skjnldsv]

Hello! I will need your browser console log to investigate this issue. Open your console, reload your page and/or do the action leading to this issue and copy/paste the log in this thread.

How to access your browser console (Click to expand)

Chrome

• Press either CTRL + SHIFT + J to open the “console” tab of the Developer Tools.
• Alternative method:
  1. Press either CTRL + SHIFT + I or F12 to open the Developer Tools.
  2. Click the “console” tab.

Safari

• Press CMD + ALT + I to open the Web Inspector.
• See Chrome’s step 2. (Chrome and Safari have pretty much identical dev tools.)

IE9

1. Press F12 to open the developer tools.
2. Click the “console” tab.

Firefox

• Press CTRL + SHIFT + K to open the Web console (COMMAND + SHIFT + K on Macs).
• or, if Firebug is installed (recommended):
  1. Press F12 to open Firebug.
  2. Click on the “console” tab.

Opera

1. Press CTRL + SHIFT + I to open Dragonfly.
2. Click on the “console” tab.

[knuxify]

@skjnldsv Updated the original issue and added the browser log.

[Mikescops]

@skjnldsv can you move this to the viewer repo?