Skin mods (usually weapon worldmodel and infected skins) can cause problems when playing on local servers if the host server's CVAR of sv_consistency is set to 1.

Users may assemble multiple add-ons in Collections, so the others can instantly subscribe to all the add-ons from these at once. One can also add an item to their Favorites by clicking on the heart sign in order to easily find it later. The items can also be sorted by the number of subscribers, popularity, the date of release over a specific time period. One can use multiple tags to search needed items. On the downside, it does require a constant network connection to use the addons, though the game does not need a connection to play offline. Furthermore, if a user has multiple devices, it will download the mod to any that the user downloads Left 4 Dead 2 to, so long as they use the same Steam account. This made acquiring addons easier since it automatically updates the addon when needed, unlike manually placing one.

These can be downloaded by clicking 'subscribe' and deleted by clicking 'unsubscribe'. The Workshop is split into various categories, such as Custom Campaigns, weapon/skin mods, sound mods, UI mods, and other kinds of modifications. It was introduced after the Februupdate along with most other games such as Counter-Strike: Global Offensive, Team Fortress 2 and notably Garry's Mod.

Left 4 dead mods