I was just wondering if Flarum or its huge library of extensions can add these features to Flarum.

  1. Select image to upload. Instead of displaying the markdown format for adding an image, display a file picker for users to upload a file. (I don't care where the image is stored, whether locally or on a dedicated free image storage provider)

  2. Post Preview. The ability to toggle a panel that displays a preview of the post currently being created or edited. I find this is the feature I use the most on Discourse forums.

  3. Community Moderation. The ability for community members with select badges/within certain groups to 'hide' a post when it is flagged. The post would be replaced with text like "This post has been hidden. Click to view it". When a Mod/Admin comes online, they can decide to leave the post in its 'hidden' state, delete it, or show it normally again.

  4. Creating Topics and Templates. When creating a post, it would be nice if the user was forced to choose a tag, and an Admin can define a template for each tag. For example, if the "support" tag was selected, the text "Make sure to include the error message" would be added to the editor, and if the "Informal" tag was selected, the text "This tag is not for support requests!" would be added to the editor.

Just my thoughts, please let me know if any of this is possible!

    Greenreader9 Select image to upload. Instead of displaying the markdown format for adding an image, display a file picker for users to upload a file. (I don't care where the image is stored, whether locally or on a dedicated free image storage provider)

    You can actually do that with FriendsOfFlarum Upload, when you use the right template to display uploaded images.

    Greenreader9 Post Preview. The ability to toggle a panel that displays a preview of the post currently being created or edited. I find this is the feature I use the most on Discourse forums.

    When writing a new post reply there is already a preview in place. For starting a new discussion there is not, but there is already a feature request for that. Also you might want to check out the WYSIWG editor as it achieves parts of that?

    Greenreader9 Community Moderation. The ability for community members with select badges/within certain groups to 'hide' a post when it is flagged. The post would be replaced with text like "This post has been hidden. Click to view it". When a Mod/Admin comes online, they can decide to leave the post in its 'hidden' state, delete it, or show it normally again.

    There is no such extension available at the moment.

    Greenreader9 Creating Topics and Templates. When creating a post, it would be nice if the user was forced to choose a tag, and an Admin can define a template for each tag. For example, if the "support" tag was selected, the text "Make sure to include the error message" would be added to the editor, and if the "Informal" tag was selected, the text "This tag is not for support requests!" would be added to the editor.

    There are already two extensions available for that, one open-source (FriendsOfFlarum Mason) and one premium (Formulaire).

    Hope this helps as a start!

              Greenreader9 Do you know if one is in creation, or if there is a place I could suggest it?

              Yes, you can create a request under the Feedback > Features tag. I don't know that anyone is working on something like that at the moment. If this feature request comes from a spamming perspective, you might find our community post interesting and see all moderation options available.