Do you have a strange label in the sidebar in Gmail called smart_label_root_name? It is a rare problem that sometimes appears for no reason. Remove it using a secret access mode in Gmail.
Although this article focuses on a specific problem, along the way to fixing it you will see how to manage labels in Gmail, hiding them or removing them if you no longer want them. We will also look at a little used and little-known access mode for Gmail that turns out to be the only way to get rid of the pesky ‘smart label root name’ label. It might be useful for fixing other problems in your Gmail account and it is useful to know.
Manage labels in Gmail
Move the mouse over a label in the sidebar in Gmail and then click the three dots to access a menu. You can show or hide labels, but a useful alternative is Show if unread. This means that the label only appears in the sidebar if there are unread emails with it attached. You can also set a color, which is really useful for making labels stand out in the inbox.

Down near the bottom of this label menu is Remove label. Don’t worry, clicking it does not delete any emails and it just removes the label from them. The messages are otherwise unchanged and stay in your inbox.
smart_label_root_name

This strange label may appear in the sidebar in Gmail and I do not know what causes it. Maybe it is a bug in Gmail. Click the three dots next to the label and instead of the usual label menu, there are simply Show and Hide options, which actually do nothing. The label remains whatever you select. Notice that, unlike the regular label menu, there is no option to delete this one.
Manage labels in Gmail Settings
The next obvious place to manage labels is in Settings. Click the gear icon in the top right corner in Gmail and click See all settings at the top of the panel that is displayed. Select the Labels tab at the top and then look down the list of labels for smart_label_root_name. Click the remove link on the right.

Here you can see at the top of the screenshot that the label was not removed. This is an awkward label that Gmail refuses to hide or remove. It is very odd and the name looks like something a programmer would use.
Use Gmail html view
The normal Gmail view uses advanced features of modern web browsers to access and display your email. For people that are using simpler, older web browsers with fewer features, there is a plain html view. I don’t know how many people use it and I suspect there are few. Most people don’t even know html view is an option and once you have tried it, you won’t want to use it as your default view, it is pretty awful. However, it does allow us to delete that unwanted label.
Assuming your web browser automatically logs into Gmail and shows your inbox, instead of the usual URL, type https://mail.google.com/mail/u/0/h/ into the browser’s address box instead.

Your Gmail inbox appears, but in a very plain and simple view. Labels appear in the sidebar as usual and at the bottom is an Edit labels link. Click it. All the labels are listed and there is a Remove button that deletes any label you do not want. For some strange reason, this button does actually remove smart_label_root_name where the other methods fail.

That’s it. You can close the browser tab and go back to accessing Gmail in the usual way, but without that annoying label.
Here we looked at the label menu for showing, hiding and removing labels, the Labels tab in Gmail Settings, and also how to access Gmail using plain html, which can solve problems with regular Gmail access. These are all useful things to know.