a number of times, you will see that sunnis will presume that if someone is a sahabi, it means he is going to heaven without even being asked
or they would say that their bad deeds are forgiven for sure
or that it will not affect them at all

for them, only sahabiyat/companionship of holy prophet asws is good enough for entry to heaven

but let us see the opinion of umar in this regards

we find in sahih bukhari

Volume 5, Book 58, Number 254 :

Narrated by Abu Burda Bin Abi Musa Al-Ashari
‘Abdullah bin ‘Umar said to me, “Do you know what my father said to your father once?” I said, “No.” He said, “My father said to your father, ‘O Abu Musa, will it please you that we will be rewarded for our conversion to Islam with Allah’s Apostle and our migration with him, and our Jihad with him and all our good deeds which we did, with him, and that all the deeds we did after his death will be disregarded whether good or bad?’ Your father (i.e. Abu Musa) said, ‘No, by Allah, we took part in Jihad after Allah’s Apostle , prayed and did plenty of good deeds, and many people have embraced Islam at our hands, and no doubt, we expect rewards from Allah for these good deeds.’ On that my father (i.e. ‘Umar) said, ‘As for myself, By Him in Whose Hand ‘Umar’s soul is, I wish that the deeds done by us at the time of the Prophet remain rewardable while whatsoever we did after the death of the Prophet be enough to save us from Punishment in that the good deeds compensate for the bad ones.’ ” On that I said (to Ibn ‘Umar), “By Allah, your father was better than my father!”

[sahih bukhari, online link]

so, what we find from this narration is

1- for umar, it is not the sahabiyyat, rather the deeds which count.

2- if sahaba have done bad deeds, which are not compensated by good ones, they may well be punished. only if the good deeds compensate for bad ones, they ll be safe from punishment

3- umar accepted they did good deeds in lifetime of holy prophet, and wished that they remain rewardable; but, but, but, he accepted that what they did after prophet, their is a question mark on that………………….