I troubleshooted this issue today and discovered that GTK3 is not correctly discovering the AT-SPI bus that allows Anaconda to connect to Orca. I’m not sure why it’s happening, but I’ve submitted a patch to work around the issue to Anaconda.
For now, you can work around this in variants like Fedora KDE Plasma Desktop by going into to the terminal and running the following commands:
export AT_SPI_BUS_ADDRESS=$( busctl call --user org.a11y.Bus /org/a11y/bus org.a11y.Bus GetAddress | sed 's/s "\(.*\)"/\1/' )
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