AdiIRC vs WeeChat

AdiIRC is constantly being developed and improved. It's among the most actively developed IRC clients nowadays, with a great beta team behind it. The changelog shows multiple substantial releases every month.

Nick Column feature support too.

It's a free IRC client supported by donations.

It works perfectly with Windows 10, has all the needed functions like:
1 - handle all irc:// links.
2 - start with windows.
3 - start minimized.
4 - close to tray icon when pressing X(close button).
5 - it can open all the channels in one window or open each channel in new windows (it is up to you).
6 - tons of options to pick up from.

Configurations, scripts and snippets are saved within the installation folder, allowing you to easily move them to a different installation. It also means that nothing is changed in your system.

Does not create registry keys.
Does not create any other folder than it's own on any other location.
Even when the installer is used, you can make it portable by just moving the folder around, don't need to worry about anything else.

Feature requests, suggestions and bug reports get prompt feedback.

A portable version is also available in the download section. It can be run without installation allowing it to be run off of external devices such as USB sticks.

You choose, Simple or Complex layout. Check the screenshots section in here.

miRC themes also works well in AdiIRC.

Supports Foobar2000, Winamp, QCDPlayer, iTunes, MusikCube, MediaMonkey, XMPlay, Spotify, VLC Media Player, Media Player Classic, MusicBee, PotPlayer and SMPlayer.

The vast majority of mIRC scripts/snippets work in AdiIRC, with compatibility constantly being improved.

Unlike hexchat, which needs to manually add a script.

Inline support for custom emotes and icons. Adding , removing or editing images replaces whole chat buffer tags in real time. AdiIRC makes your irc experience much more fun.

Plugins support too, with certain scripting languages to write.

Spellcheck for over 120 different languages is available. Full list of languages can be found here.

The user interface has full internationalization support and the developer is quick to integrate translations created by users or other contributors. Currently, full translations are included with the standard installation for Danish, German, Polish and Brazilian Portuguese.

The application can be configured to search for available updates at user-defined intervals for both the Stable and Beta release channels, and provides a dialog which automatically retrieves the updated installer and launches it.

You can modify or add your own hotkeys to your desire function.

You can monitor any event you like via a dockable panel that will record and optionally notify you upon detection of anything matching the set criteria.

The standard installer includes several standard color schemes to choose from, and it is possible from within the Options dialog to export any that you customize or create to share with others, or import those shared by others. The syntax of the file which defines them is well-documented and can be modified in any text editor if desired.

The client weighs less than 1MB.
Low CPU usage. Almost no CPU usage, in fact...

IRC is still very much alive and the protocol specification continues to evolve with new features and standards developed and published by the IRCv3 Working Group. As part of their work, they track the adoption and implementation of the specification they publish, and they announced on their website that as of the release of AdiIRC v3.9 on September 30, 2020, it was the first IRC client they were aware of to correctly implement support for all of the features in the current IRCv3 spec. This was accomplished only five months after two of the major IRCd servers (InspIRCd and Oragono) had released versions implementing all of those same features.

WeeChat has a command line interface.

WeeChat has an easy to use interface and sane defaults, making it a great client for beginner users.

Easy to configure weechat connect to server using certificates

Many dotfiles are publicly available.

Weechat allows very flexible window splitting behavior to show multiple IRC channels at once. Windows can be split vertically and horizontally.

Weechat can be fully driven by keyboard shortcuts. Navigating between buffers, switching between windows and changing text styling can all be achieved with keyboard shortcuts.

Supports scripting in C, Python, Perl, Ruby, Lua, Tcl, Scheme and Javascript.

Works perfectly with a poor connection.

Smart filtering lets set a series of rules for IRC channels. For example, it allows instructing the client to show /quit and /join messages only if the user was speaking in the last 20 minutes.

WeeChat is a free program licensed under GPL with source code available on GitHub.

It's possible to leave WeeChat running at home/on a server, then connect to it with a smartphone client. This way a choppy mobile internet connection won't disconnect from IRC, and still allow using a touch screen optimized UI.

Weechat community can be found on #weechat @ Freenode. The community, including devs, is helpful in answering any WeeChat related questions.

WeeChat has a built-in tool for searching, downloading, installing and updating scripts and plugins.

By default WeeChat has a chat area surrounded by a nicklist on the right, title bar on top, and status and input bars at the bottom. The layout, though, can be completely customized and split vertically or horizontally. It supports 256 colors as long as the terminal supports 256 colors as well as bolded, italicized and underlined text. Even includes little touches as differently colored nicknames for people /away.

WeeChat scripts repository has hundreds of scripts including url shorteners, music player integrations and bandwidth monitors.

Mouse click and gestures are supported on a local terminal as well as remote terminal accessed via ssh regardless of screen/tmux. To enable mouse support use /mouse enable command or press alt+m.

You are able to modify configurations inside application or via modifying files(i.e. colors).

WeeChat has html5, qt, android, emacs and javascript remote interface options.

Text is searched through in real time as search terms are being written.