TYPO3 - Images cannot be used

I have a TYPO3 version 11.5 and I can no longer add images to a data record or content element. When I click on "Add image", a layer opens. This remains white. In the browser console I see that "preview files are being loaded. There are probably too many images in this folder. 895 PDF files and 126 images with a total of over 700 MB.

How can this be solved? By moving the files to another folder? If I move the PDF and image files, they no longer have a link to the data record, right?

Normally TYPO3 does not load all 895 files here, but only accesses the data records generated for the data via the File Abstraction Layer (FAL). The files themselves are only accessed if (meta) data has to be entered directly or the file has to be processed directly.

There are two main reasons why loading times can be too long:

1. thumbnail generation

Especially with (large) PDFs, it can be quite time-consuming to generate a thumbnail. If this has to be done in parallel for many PDFs, this puts a strain on the server - and depending on the performance/account, the process reaches its limits. One solution here could be to deactivate thumbnails in the backend:

2. extract metadata

If there are (many) new files, extracting the metadata or creating the FAL data records on the fly can also be too resource-intensive. Two scheduler tasks could do this in the background - once, or if files/PDFs are regularly uploaded via FTP/IMporter/... can also run periodically.

• File Abstraction Layer: Update storage index
• File Abstraction Layer: Extract metadata in storage