To clarify, I have the following routes:
Route::get('/mytest', 'TestController@showForm');
Route::post('/mytest', 'TestController@postForm');
In "TestController::showForm()" I set a session variable with some data about the user's state when they started the test. I could put this in a hidden form field but I prefer to keep this data outside the form.
In "TestController::postForm()" I want to be able to retrieve the aforementioned data about the user's state .
What I have had to do is use normal session data and then delete the session data myself - I tried using "flash()" but it didn't work if the user had my website open in another tab and then did something in that other tab between being shown the form and posting the form (ie if they did something in the other tab while considering what data to enter into the form they have been shown).
Therefore my question was a general one as to whether this was a known limitation of flashing session data, or whether there is another way around this that I haven't thought of.