I could have fished for a counterspell, but couldn't activate the ability of an artifact under the stack. This is potentially match warping depending on the situation. Unlikely, but frustrating when it matters.

Another screenshot of the issue. Tapped the Stack several times before finally getting blue mana!

Having an issue with Mobile UI elements being blocked by the Stack in certain cases. This is an ongoing issue that has been posted in the past and still not fixed years later.
The Stack kept getting in my way from selecting blue mana shown in the photo.
Also happens with Lotus Cobra if they are on the far right.

Suggestion to fix: as previously mentioned by other players a button to hide the Stack entirely would fix this issue. Instead of the pull-out arrow make it an eye icon or something and hide the Stack into a smaller button on the right side screen, similar to your "leave match" button when viewing the field after the match.
Alternatively add new button next to friends and options.
Playing Mobile on Android, Galaxy S20.

STILL A VALID ISSUE IN 2023!!
I also had a similar issue with the new Chandra planeswalker. The Stack kept getting in my way from selecting blue mana.
Also happens with Lotus Cobra if they are on the far right.
Playing Mobile on Android, Galaxy S20

I can't read cards on the stack and it has cost me the game, at least a couple of times. If someone plays a spell, and that triggers a character ability, it immediately put the ability on the stack above the spell. Then I can't read what the other players spell was, because it happens so fast! I don't know if I want to use my negate or not, or if I want to copy that spell or not. And the game doesn't give you enough time to go look the card up somewhere else. Sometimes you can hover over the card on the bottom of the stack and it will turn orange border, but no amount of clicking it will reveal what that card says!

CRITICAL FLAW! NEEDS IMMEDIATE FIX!

This is a critical issue and need to be patched asap like how hard would it be to just make an eye on the stack so you can hide it and make it appear again like they are already doing for other things

This is still an issue in 2022. I flashed in the Wandering emperor to exile his golden dragon after it attacked, and he played a fading hope that then went on the stack and blocked me from seeing my wandering emperor and thus exiling his card. This is a very simple fix to an issue that shouldn't happen with a game as big as this.

I just had the same problem in historic brawl. I played seal away and was trying to see what was exiled under an enchantment spell because i honestly forgot what card was exiled. After confirming the card and realizing i didnt want to free it but target another permanent i was unable to get it of the view page. I tried to to view other cards or close the viewer but it wouldnt let me. This has happened to me multiple times as well.

log file from previous comment

I absolutely agree . Although this has happened many times before, the latest just happened in my previous game, thus causing a loss. I had Heliod, Sun Crowned on the battlefield along with a Alseid of Life's Bounty. My opponent had a Sprite Dragon and a few other cards on the battlefield.

MY opponent played some card that targeted my Heliod. The only way I knew this initially was because, for whatever reason, people have a need to "touch" a card right before they target it, so it lit up. Immediately upon playing this mystery card, their Sprite Dragon's ability triggered and a copy of sprite dragon was put on top of their initial spell. I tried in vein to see what the card was and to verify its target. I did learn that if you click the card in question, an arrow comes up pointing to its target. Fantastic.
At this point, I elected to pay 1 and sacrifice my Alseid resulting in triggering its ability. The protection ability requires me to choose the color in which I want my chosen target to be protected from.

Because the initial spell my opponent cast was immediately covered up by sprite dragon, I did not see what color the spell card was. All I knew at this point was that my opponent had red, white, and blue manna available. I guessed the card was probably Crush Contraband or True Loves Kiss, both of which are white. I guessed white since even the cards border did not help. As it turns out, their spell resolved and my Heliod was put back in my hand. It was a blue card.

Because of the spells success, I was not able to give one of my remaining creatures lifelink which then allowed my opponent to deal lethal damage on their next turn.

I have filed reports before on the issue of cards magnifying and blocking view of other cards (this still happens when deck building). Being able to move objects out of the way is so common in gaming that a program edit should be feasible and not overly complicated. If the concern is which card is in what position on the stack, you could have a number such as one for top two fr the next one down,, etc placed on each card as a transparent number or something like that.

Please fix this problem as it literally gives unfair advantage to the player initiating the spell and thus makes the game all but unplayable.

Thank You