Is it possible to show images in title? Is it possible to increase title character length to more than 255? If not, then how can those be achieved? Plugin, core modification, any ideas? Thanks.
Are you talking full
png images in the title? That would be a plugin for sure, and likely quite complicated. Depending on where you want this image to display, you may be looking for the Topic List Previews plugin.
That would also need to be a plugin -
but this one is simple. See GitHub - jomaxro/discourse-plugin-site-setting-override for an example of how to override a site setting.
Important Note: See Régis’s reply below. This is not a simple plugin anymore due to the size limit in the database.