I haven't seen an option on this in Editor settings, but my personal expectation as a developer would be that it probably should. I sometimes have quite a bunch of tabs open with specific sets of files, and restoring them from the side-panel isn't the most straight forward.
Case in point:
This is what my current session looks like:

I'm now restarting Godot. This is the active tab now:

I want to press one of the + buttons to create a split - however they are all disabled:

I need to double-click and open a file from the side panel to get the buttons to enable and be able to create a split. I'm expecting the buttons enable on an open file sort of signal - which isn't getting fired or is not caught when the IDE is first opened
I haven't seen an option on this in Editor settings, but my personal expectation as a developer would be that it probably should. I sometimes have quite a bunch of tabs open with specific sets of files, and restoring them from the side-panel isn't the most straight forward.
Case in point:

This is what my current session looks like:
I'm now restarting Godot. This is the active tab now:

I want to press one of the + buttons to create a split - however they are all disabled:

I need to double-click and open a file from the side panel to get the buttons to enable and be able to create a split. I'm expecting the buttons enable on an open file sort of signal - which isn't getting fired or is not caught when the IDE is first opened