Voting
Voting
[Cueball walks in from right, staring at his phone and talking to Megan.] Cueball: I will crawl across broken glass to vote this year if I have to. Megan: ...Why would there be broken glass? Megan: There aren't even any big windows at our polling place.
[Cueball raising a finger triumphantly.] Cueball: I will wait in line till the sun burns out. Megan: Ok, some places have lines, which is awful, but it's usually pretty quick here? Megan: Definitely not 5 billion years.
[Cueball raising a fist.] Cueball: I will walk barefoot across hot coals to cast my ballot! Megan: Where would you even find coals? Megan: You can wear shoes to vote. This scenario makes no sense.
[Cueball raising a finger, and walking back off-panel to the left] Cueball: I will swim across a shark-filled channel! Megan: That'll take you way outside our precinct. Cueball: Then I'll swim back! Megan: Can you do all this stuff after voting?

The run-up to the 2020 United States elections , occurring on November 3, 2020 (less than 2 months from the time of the comic's publication), has been fraught with various overlapping worries about the legitimacy of the forthcoming result. The COVID-19 pandemic has created a new interest in voting by mail , at a historically large scale. See Postal voting in the United States for more detail. Cueball, however, is in a very patriotic mood and makes a series of hyperbolic statements to Megan about the trials he would be willing to endure in order to vote in the upcoming elections, none of which would (hopefully), in reality, apply to his or anyone else's circumstance.
Crawling across broken glass might have actually been necessary at some polling sites of the 2001 New York City mayoral election primary, which had begun on September 11, 2001, and would have continued had it not been postponed two weeks due to the terrorist attacks of that day. However, as Megan states, their polling sites, unlike those of the 2001 election, don't even feature any especially large windows or other such structures from which broken glass could be derived. The idea of being so intent on doing something (in this case, voting) that a person claims to be willing to crawl across broken glass to do so is a common expression.
The Sun, currently a yellow dwarf star on the main sequence, will eventually expand into a red giant, then collapse down to a white dwarf when its fuel is exhausted; this will not happen for billions of years, as Megan points out. Because of this, waiting until the sun burns out would result in Cueball's vote not being counted at all, both because it would be after the official deadline for ballots to be cast and because there would no longer be anyone alive on Earth.
As Megan observes, hot coals would most likely not even be present at their polling stations, and although some states have been accused of trying to make voting inconvenient or unsafe, this comic has not yet led any states to prohibit wearing shoes at polling places.
According to Megan, her and Cueball's municipality does not even include a single shark-infested body of water that Cueball would be able to swim through in order to cast his vote. Cueball's solution to this problem is to simply swim back to their location after swimming in his shark-filled channel.
Megan tries in vain to convince Cueball that his proposed actions are unnecessary or even impossible in their area, but, unable to bring him back to reality, she closes the final panel by asking if he'd be willing to put off all of this dangerous stuff until after voting, perhaps so that he will be alive long enough to vote in the first place.
Broken glass, the extinction of humanity, hot coals, and sharks aside, though, Cueball faces the risk of contracting COVID-19 from being in such close proximity to so many other voters, as he seems to plan on voting in person (his words show his desire for activities only possible by way of physical action; in the title text, he also ignores Megan when she says that mail-in voting is available).
In the title text, Megan tells Cueball that he does not need to go to such lengths to vote, as their state has mail-in voting and already sent forms either to cast a ballot or to apply for mail-in ballots. Cueball ignores her and continues looking online for shark-filled channels to swim through.  In doing so, he completely negates his professed desire to vote, as he is ignoring the easy path and going after paths that would end up making it impossible to cast his vote. Alternatively, he may just be caught in the normal rabbit hole of doing Internet research, where you start researching one thing (voting locations) and end up reading about another (locations of shark-infested channels).
Randall is making the point that, despite apparent obstruction tactics and threats and attempts to de-legitimize the process, voting is very important (Cueball is using hyperbole to illustrate the importance), and relatively easy (as Megan keeps reminding him).  He is also expressing an opinion that the increased danger of system compromise harming the legitimacy of the voting process due to massive mail-in voting is less worrisome than the corona-virus pandemic keeping people from voting at all, if in-person voting were the only viable option.
Randall lives in Massachusetts, a state with majority Democrat media, voters, and government.  Sharks are sighted off Cape Cod on occasion, so if he really wanted to, he could swim with them, but unless he lives on Cape Cod itself, it would take him very far outside his voting district.
[Cueball walks in from right, staring at his phone and talking to Megan.] Cueball: I will crawl across broken glass to vote this year if I have to. Megan: ...Why would there be broken glass? Megan: There aren't even any big windows at our polling place.
[Cueball raising a finger triumphantly.] Cueball: I will wait in line till the sun burns out. Megan: Ok, some places have lines, which is awful, but it's usually pretty quick here? Megan: Definitely not 5 billion years.
[Cueball raising a fist.] Cueball: I will walk barefoot across hot coals to cast my ballot! Megan: Where would you even find coals? Megan: You can wear shoes to vote. This scenario makes no sense.
[Cueball raising a finger, and walking back off-panel to the left] Cueball: I will swim across a shark-filled channel! Megan: That'll take you way outside our precinct. Cueball: Then I'll swim back! Megan: Can you do all this stuff after voting?
