This mod supports configuration and will upon first use create a properties file at .minecraft\config\ChatLog.properties. This file currently contains two configurable settings:
max_logs: The maximum amount of logs the mod can store. The mod creates one new log per day Minecraft has been played and has received chat. Setting this to 0 will store only today’s log, and setting it to -1 will store an infinite number of logs. The actual amount of logs stored by the mod might vary slightly. If you want to limit the mod to a strict maximum value you should set it to 1 lower than your intended value. If you set the value to 40, it will store the last 40 logs. If it’s the first time per day you play Minecraft, it will generate a 41st log, but it will reduce to 40 on next launch the same day.
color_pack: Which color pack to use. Current available color packs: 0 (default) and 1 (dark). Changes to the color pack will not affect already received messages and logs.
enabled: Whether or not to log anything at all.
filters: Don’t edit this manually. Contains filtering information for ChatLog. Edit in-game using //cl filter (type “//cl filter?” for help).
logflags: Whether or not to log message flags (F = filtered message, S = control message (system message))
As new updates come, new options may be included. This will be listed in the changelog at the bottom of this post. If the mod cannot find these settings in the properties file, it will use a default value. To configure newer settings, it is recommended that you reset the configuration by deleting it (also, keep a backup). Directly adding the new options to the configuration file might work, but can produce unexpected result and even game crashes. (To fix this, undo your changes or delete the configuration file.)
Where are chat logs stored?
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Chat logs are stored in the ./chatlogs folder of .minecraft_classic. To find this folder, on Windows; press Ctrl+R, enter “%appdata%/.minecraft_classic/chatlogs” and press Enter. On Mac, navigate to ~/Library/Application Support/minecraft_classic/chatlogs. On Linux, navigate to ~/.minecraft_classic/chatlogs.