UPDATE: Tom has now added the Undetermined language option to our instance. To make sure you can see the majority of Lemmy content from within your feddit.uk account, do the following:
Click your profile name - click settings - scroll down to the Languages box (not interface language) - hold down Ctrl (cmd on Mac) and select both English and Undetermined. On mobile browser: Tap the Languages box and make sure both are selected - scroll down and click save
You can also select any other languages which are beneficial to you.
If you don't see everything listed in the box, try refreshing the page.
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Original Post
When viewing profile settings, you will see a box which says:
Warning: If you deselect Undetermined, you will not see most content.
On feddit.uk we currently have no selectable language option other than English. This means that (sometimes?) we will not see a lot of posts / comments on other instances / communities where the OP did not specifically select English before posting
See also: This Lemmy documentation under 'Setting up your profile'
• Languages: Select the languages that you speak to see only content in these languages. This is a new feature and many posts don't specify a language yet, so be sure to select "Undetermined" to see them.
Ideally, we need the ability to select English (or whatever language) AND undetermined - you can select multiple, as long as they are available.
When I view X community@instance from my lemmy.world account (with Undetermined language selected in profile settings), I can see all posts and comments. When I view the same community@instance from my feddit.uk account, there are missing posts and often 0 comments on everything. This needs addressing if possible!
I'm afraid I have no idea, sorry! Hopefully someone else will know or you can find info online. I don't have a community of my own to check.