I haven't used it for a while but notice its gone.
Yes. There was a change to replace it with the 3d Experience platform. It should be installed by default in 2020 sp3.
2020 SOLIDWORKS Help - Task Pane
"Beginning with SOLIDWORKS 2020 SP 1.0, '3D EXPERIENCE Marketplace' is available with SOLIDWORKS installation and can be installed through the Installation Manager.For earlier versions, SOLIDWORKS® does not install the ‘3DExperience Marketplace’ software by default. To obtain and install this software, follow these steps:
1. From the SOLIDWORKS Customer Portal, go to ‘Downloads and Updates’ > ‘Free Tools’.2. Specify your product version > select and download the product '3DExperience Marketplace for SW'.3. Extract the file and run the setup file.4. Start SOLIDWORKS.
The installation program adds ‘3DExperience Marketplace' to the task pane from which you can log in and explore the resource."
There is an enhancement request to add info to the help documentation about it. Please vote if you can.
SPR 1184893: Update the information in 'SOLIDWORKS Help' about '3D ContentCentral’ is no longer available in: ‘SOLIDWORKS Design Library’ and '3DExperience Marketplace' is required for obtaining Supplier content
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