When openin an adept with "enhanced_accuracy" the +2 bonus to attack rating is correctly shown for the weapons.
When modifying a weapon (e.g. switching Smartlink on or off), the bonus gets lost. The bonus is still not shown when leaving the weapon dialog.
Existing the character and re-loading it applies the bonus again.
That is because of two conflicting ways the "Enhanced Accuracy" bonus is implemented and not really a bug, but a side effect of the current way it is implemented.
In a perfect world, the modification from "Enhanced Accuracy" would never appear in the weapon modification dialog, since it is not a property of the weapon itself.
Unfortunately whenever the character is loaded or recalculated, the effects of the adept power are stored on top of the calculated weapon. That is all fine, until changes are made to the weapon and the weapon is recalculated and the on-top modifications are cleared -> until something in the character changes.
So, this isn't really a bug, but a necessity of the current architecture, which leads to a minor inconvenience.
This also means: changing this, requires a complete rewrite of all modification handing for Shadowrun and that is A MAJOR change.