On the comics formatting - long vertical posts is very standard for tumblr! On mobile the read more is a text button just like twitter. The expand is actually a newer UI addition, and doesn't exist on web (as far as I know) - it's just a setting on mobile that shortens long posts if the user that setting toggled on.
Also as a warning if you plan to link to a masterpost, 1st part, next / previous part, etc. Tumblr is sometimes weird with posts that have links, so it's recommended to edit your post and add the links in after initially posting.
If you want to keep a record of all the parts (like the Twitter moment), usual practice is to make a masterpost with all the links, or make a separate page on your blog that links to the tag for the story. The separate page may not display properly on the mobile app if you've got a web theme on your blog though.
((@zarla-s is someone who's been on here for ages and has one of the most well-established comics around the Undertale fandom if you want to see usual formatting for comics on tumblr! She has a web theme too.))
Sorry for the long ask, but I saw your post about how to orient the comic pages. Hopefully something in here was helpful, just wanted to share my input as someone who's very familiar with tumblr. I loved your works on Twitter and am excited to relive it on here and instagram. Hope your new accounts will be even more successful š
ohh thank you so much this was so helpful!! having that reference rly helps as well šš














