Algebra view spontaneously resizes to full width, doesn't reset back

Part 1 of a series of bug reports for GeoGebra 6 long-standing UI issues.

In GeoGebra classic 6, open the attached file and click on the definition of l1 in algebra view in order to edit it.

The algebra view resizes to full width of the window. It does not snap back to original width after editing is done, resulting in the 2d view disappearing.

The sash that separates the algebra view from the 2d view disappears too - it is pushed out of the window's client area.

The only way to get the 2d view back is to shrink the entire window (browser or desktop app) and maximize it again. Doing so is necessary every time an object whose rendered formula is very wide is edited in the algebra view. It doesn't have to be a very long sequence with length in the thousands; it can simply be a very long formula, or a sequence of just a dozen real numbers when display precision is set to 15 digits.

Expected behavior: the width of the algebra view should be kept steady, unless the user intentionally resizes it by dragging the sash, or the window is resized, in which case proportional resizing may apply.

EDIT: this minimal repro doesn't demonstrate the whole issue. Yes, the algebra view does snap back to the original size when the definition editing mode is exited by clicking on the white area under the last item of the algebra view, or on the new item prompt. It doesn't when I click on the toolbar. However, when the algebra view contains many items and it is auto-resized to full width, the toolbar is the only part of the window that isn't the algebra view and is readily available. The white area under algebra view is not available because the algebra view is full, and the new item prompt is often not scrolled into view