Given that the latest release for Sidewise is from 2014, you need to open source your code if you want to see any improvement on this.
There don't seem to be any extensions which can compete with how Sidewise docks next to Chrome, so I believe you should do something to help with the innovation of this extension.
Open source your code, or remove the clause which prevents people from hosting on the Chrome store, since it's the only way people can "distribute" anything they "modify" and not have it disable itself the next time Chrome restarts.
For anyone who hasn't seen the license, here is the relevant parts of it:
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, and/or distribute copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The Software and any software derived from it may not be published via the Chrome Web Store at https://chrome.google.com/webstore without specific prior written permission.
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