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Tab-related options

Tabs appear right below toolbar icons; they give you quick access to currently opened windows.

First set of choices

Let DC++ draw tabs: Select this option to let DC++ draw tabs, which allows it to add more customization (such as a close button, different colors and fonts, etc). (default)
Use standard Windows tabs: Select this option to use standard Windows tabs - DC++ won't be able to customize them.
DC++ needs to be restarted for this setting to take effect.

Second and third sets of choices

Several modes are exposed here with various differences; select the one you prefer.
One particular difference is that in tab style mode, multiline tabs re-organize so that the selected tab is always at the bottom. That isn't the case in button style mode.
DC++ needs to be restarted for this setting to take effect.

Tab width

Use this slider to define the width occupied by each tab. Move to the left for a lower width, and to the right for a higher width.
When the title of a tab exceeds the available width, it will be cut accordingly and appended with "...".
DC++ needs to be restarted for this setting to take effect.

Preview

This fake tab control shows how the main tab control would display after a restart of DC++, were the settings defined above be validated.

Tab highlight on content change

Hub
When a chat message appears in a Hub window that's not focused, the tab will be highlighted if you have this option selected.
Private message
When a private message appears in a Private message window that's not focused, the tab will be highlighted if you have this option selected.
File List
When the content of a File List window that's not focused has changed, the tab will be highlighted if you have this option selected.
Search
When a search result is received in a Search window that's not focused, the tab will be highlighted if you have this option selected.
System log
When an entry is added to the System Log window while it is out of focus, the tab will be highlighted if you have this option selected.
Download Queue
This option controls whether or not the Download Queue's tab will highlight itself when a queue item changes state or finishes.
Finished Downloads
When a download completes, the Finished Downloads tab will be highlighted if this option is selected.
Finished Uploads
When an upload completes, the Finished Uploads tab will be highlighted if this option is selected.