Image uploading not working on products on 2.3

[mikelmao]

Preconditions (*)

1. Magento 2.3 Community

Steps to reproduce (*)

1. Install a fresh copy of magento 2.3 community (im running it on Ubuntu)
2. Create a product and attempt to upload an image

Expected result (*)

1. Image should be uploaded and linked to the product.

Actual result (*)

1. The following error appears: A technical problem with the server created an error. Try again to continue what you were doing. If the problem persists, try again later.

2. I have tries changing "fileUploader" to "imageUploader" in app/code/Magento/Theme/view/adminhtml/ui_component/design_config_form.xml
   This allowed me to upload logo images again. So I'm assuming this needs to be done as well somewhere else?

[magento-engcom-team]

Hi @mikelmao. Thank you for your report.
To help us process this issue please make sure that you provided the following information:

• Summary of the issue
• Information on your environment
• Steps to reproduce
• Expected and actual results

Please make sure that the issue is reproducible on the vanilla Magento instance following Steps to reproduce. To deploy vanilla Magento instance on our environment, please, add a comment to the issue:

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where $VERSION is version tags (starting from 2.2.0+) or develop branches (for example: 2.3-develop).
For more details, please, review the Magento Contributor Assistant documentation.

@mikelmao do you confirm that you was able to reproduce the issue on vanilla Magento instance following steps to reproduce?

• yes
• no

[magento-engcom-team]

Hi @engcom-backlog-nazar. Thank you for working on this issue.
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Hi @mikelmao thank you for you report, this issue has already fixed on 2.3-develop branch. also please look #19988