Opening an attached image that seems to be uploaded (possible character issue in the filename)

## Problem description

Clicking an image to have the "big" version of it leads to an error message.

## Steps to reproduce

1. Seen in the first post of construct.net/forum/game-development/game-development-design-ideas-25/help-with-lighting-mechanics-137571

2. Click the image at the bottom of the post

3.

## Observed result

"sin título-2 not a handled upload."

## Expected result

The image displayed in full.

## Affected browsers

* Chrome: yes

* Firefox: yes

* Edge: not tested

* Safari: not tested

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